2.1 Introduction
roe have long played an important role in the execution of military operations.1 At the strategic level, roe are political constraints on the use of lawful force; at the operational level, roe operate as a tool for regulating the use of force, commonly referred to as a command and control (C2) tool. As for most topics, the discussion of roe should ideally be based on a clear and common understanding of what roe are, where they come from, what purpose they have, and how they function. Although there is a general understanding of what roe are, it is difficult to find agreement on a general definition of roe, much less how they function and how they should be used. Ideally, roe should combine “top-level guidance with lower-level discretionary power”;2 however, it can be challenging to reach an agreement on how this is best achieved, especially in the multinational context of nato.
Individuals working for nato or involved in nato operations come from a variety of backgrounds, and will be influenced by various national and international understandings of the concept roe. The result is a lack of uniform understanding of roe even within nato. With only limited overviews or commentaries on the system being published, this chapter will endeavour to explain the nato roe in detail. Although the main focus will be on nato, information concerning both roe in general and other roe systems will also be drawn upon to provide a more comprehensive picture, especially in Sections 2.2 and 2.3.
2.2 Analysing roe: Definition, Scope and Form, and Legal Status
2.2.1 Definitions, Scope and Form of Rules of Engagement
Because the term ‘rules of engagement’ or roe may be used in different contexts and with reference to differing concepts, the following section will set out how the concept is perceived and applied in this book. There are two aspects to defining roe: the practical dimension of roe, i.e. what a roe should have as a function; and the formal dimension, that is, what a roe should look like or what sort of documents the roe should be found in. These will be dealt with separately, starting with some examples of how roe are defined or described in national and multinational doctrines.
Many of the explanations found of what roe are more descriptive than definitional, however. Because this distinction has limited practical implications for this book, it will not be examined further.
2.2.1.1 Multinational and National Approaches to roe
[p]art of the confusion, and arguably a solution, might be a definitional matter: namely, what is a rule of engagement? Reaching consensus on what roe are seems a logical first step toward understanding what sources should be consulted for roe guidance.3
In fact, there are several definitions of roe, with varying degrees of similarities, and those working in nato will, as mentioned in the introduction, be influenced by these differing traditions. As mentioned in Chapter 1, nato’s roe doctrine, the MC 362/1, has defined roe as “[d]irectives to military forces that define the circumstances, conditions, degree, and manner in which force, or actions which might be construed as provocative, may be applied.”4 This definition is more precise than an older nato definition of roe, namely that roe are “[d]irectives issued by competent military authority which specify the circumstances and limitations under which forces will initiate and/or continue combat engagement with other forces encountered”.5
roe appear in a variety of forms in national military doctrines, including execute orders, deployment orders, operational plans, or standing directives. Whatever their form, they provide authorisation for and/or limits on, among other things, the use of force, the positioning and posturing of forces, and the employment of certain specific capabilities.6
roe are directives to military commanders and forces (including individuals) that define the circumstances, conditions, degree, and manner in which force, or other actions which may be construed as provocative, may, or may not, be applied. roe are not used to assign tasks or give tactical instructions.9
roe are an indispensable instrument of C2 for ordering and controlling the use of force or actions which may be construed as provocative during military operations. roe are orders issued by military authority that define the circumstances, conditions, degree, manner, and limitations within which force, or actions which may be construed as provocative, may be applied to achieve military objectives in accordance with national policy and the law.11
The 2011 British Defence Doctrine similarly set out that “roe define the constraints placed upon military activities, as well as the freedoms permitted and they reflect the operational context in which it is envisaged that force may be used”.12 Finally, the Norwegian Manual of the Law of Armed Conflict states that “Rules of engagement are directives issued by competent authorities that regulate the circumstances under which military force may be used, and what type and degree of force that may be applied in those circumstances”.13
Legal scholars apply similar, though less detailed, definitions or descriptions, such as “the tools that help the military commander tailor the use of force”,14 “rules of engagement (…) specify in detail the circumstances under which fire may be opened”15 and “the set of directives given to commanders in the field to guide them on the circumstances and manner in which force may be used”.16
As these examples illustrate, there seems to be at least a general agreement on what roe are. At the centre of all the definitions and descriptions above there is the notion of a mechanism used by military forces that deals with the use of force. Furthermore, even though different words are used to describe how roe are intended to be used, for instance whether roe define, authorise, delineate, regulate, specify or clarify circumstances for, help tailor or guide the use of force, all the definitions and descriptions indicate that roe are to be used by commanders to somehow influence the use of force by persons under their command. This aspect of roe is emphasised for instance in the Canadian use of force manual, where it is explained that roe are “intended to ensure that commanders and their subordinates do not use force or other measures beyond that authorized by higher command”.17 The scope of roe as a Command and Control tool will be studied in further detail below (Section 2.5). The effectiveness of roe as a Command and Control tool would presumably be different depending on whether they are viewed as mere guidance or legally binding orders, a question that will be discussed in Section 2.2.2.
Despite this agreement on the fundamental characteristics of roe, there are also noticeable differences in how roe are viewed, in particular with regard to the scope of roe and also their form. While some definitions and descriptions only refer to the use of force, others include the regulation of other acts as well (scope). Furthermore, there seems to be some disagreement over whether the term roe refers to a set of directives or orders, or whether roe may be found in a variety of sources (form). These differences will now be looked at in more detail, together with further clarifications with respect to nato roe in particular. Finally, some conclusions will be offered on how roe should be understood for the purpose of this book.
2.2.1.2 Scope of roe
What may at first appear to be a significant difference in the definition of roe, is that some sources only include the use of force within roe, while others, such as the nato definition, also include other provocative acts. Examples of provocative acts that do not include the use of force are aspects of information operations such taking control over a radio station to distribute information intended to influence the audience; the use of jammers to interfere with mobile phone signals or navigation systems; conducting military exercises in the vicinity of an adversary’s border, and conducting simulated attacks.18 This gives the impression that the scope of nato roe is quite different from other forms of roe. However, the definitions or descriptions of roe limiting them to the use of force only may generally be divided into two categories: those provided by legal scholars and those concerning peace operations.
Legal scholars have the liberty to only include the level of detail needed for the argument they are making. The overemphasis on the use of force, to the exclusion of other provocative acts, may therefore merely be an oversimplification; after all, most roe have something to do with the use of force in some form. The focus on the use of force aspect of peace operations roe is also easy to understand. Due to the limited legal authority to use force below the threshold of armed conflict,19 roe commonly focus on the exceptional circumstances in which force may be used. However, in addition to providing guidance on the complex question of how much force may be used, the roe may also provide relatively detailed regulation of provocative measures that may escalate into a need to use force. The roe for peace keeping operations are therefore also likely to include roe regulating other provocative acts than the use of force, such as the authority to carry weapons.20
As a result, nato roe are not unique in regulating when, where, what and against whom both force or other acts which may be construed as provocative may be used.21 Thus, in addition to regulating the use of force, roe should also be expected to regulate acts such as the positioning of forces near the border of a neighbouring State; boarding of foreign vessels or aircraft; or illumination of a person or object for instance in order to track, warn off or identify. After all, a commander would want the ability to control the application of all acts which may be viewed as provocative by the opposing forces, or in any other way cause the situation to escalate. Or as the U.S. Operational Law Handbook phrases it, the roe should cover all aspects of “combat engagement with other forces encountered”;22 the ordinary meaning of ‘combat engagement’ being expected to include more than the actual use of force. nato targeting doctrine, for instance, defines ‘combat engagement’ as “actions (…) against an adversary”.23 Applying a definition that does not limit roe to the use of force therefore makes operational, or practical, sense.
Another aspect of the scope of roe is the level of detail included. roe provide the framework for when force and other provocative acts may be used and hence for the operation as such, they do not define the solutions. According to the U.S. Department of Defense, “roe should not delineate specific tactics, should not cover restrictions on specific system operations, should not cover safety-related restrictions, should not set forth service doctrine, tactics or procedures”.24 Thus, according to Roach, roe should never be ‘rudder orders’, that is, specific directions on how Commanders should use their forces.25 As Sagan explains, “roe are meant to guide commanders’ judgement about the appropriate uses of force, not to determine precisely when and how to respond to threats”.26 roe are strategic and operational command and control tools, and should therefore be distinguished from specific tactical orders.
As a result, the most commonly used historic example of roe, namely the order given at Bunker Hill on 17 June, 1775, presumably by William Prescott (“Don’t fire ‘til you see the whites of their eyes’”),27 may not actually be a roe. Instead, it is better viewed as a specific tactical order, or even a weapons handling instruction, to be executed at that time by the troops present.28 As one commentator points out, it is “too clear and too brief to qualify [as an early rule of engagement]”.29 What could have been the roe for this attack is something like ‘Attack on British forces operating on the Charlestown peninsula is authorised’. roe normally apply to more than one concrete situation and should in most cases be broad enough to cover several forces and/or available weapon systems. So, while for instance an order to await further orders before opening fire may be given to forces about to board an enemy ship or attack opposing forces, roe regulate the use of force or other provocative acts for any boarding of enemy ships or any attack on opposing forces, using any weapon not specifically regulated or prohibited. Such specific tactical orders should, of course, be in accordance with the roe. For the troops bound by both tactical orders and roe, this distinction is perhaps not too important as they have to comply with both. However, the distinction is important for the understanding of roe, and also a reminder to those who develop roe that they should not be too specific.
2.2.1.3 Form of roe
With regard to the form of roe, there seems to be a narrow and wide approach: roe being understood as certain directives or orders only, i.e. the roe serial messages (numbered one-line messages) expressly authorising or prohibiting certain acts (narrow definition); or, as any communications regulating the use of force (wide definition).30
A wide definition of roe may better reflect realities, and may be supported by the fact that most definitions of roe refer to the term “directives” rather than, for instance, ‘orders’. Guidance or instructions on the use of force and other provocative acts regulated by roe may in fact be found in a number of places. The wide approach to roe is therefore to include in the definition of roe not only the serial messages entitled roe, but also other documents such as special instructions (spins),31 standing operating procedures (sop),32 tactical directives,33 restrictive target lists (rtl),34 no strike lists (nsl),35 fragmentary orders (frago)36, and fire control measures.37 The U.S. Army Legal Lessons Learned from Afghanistan and Iraq, Volume 1 states that “[i]n addition to the authorization serials, roe also appeared in less intuitive places – places that oftentimes did not even mention “roe””.38 This wide approach to the definition of roe is clearly supported in the above-mentioned description of roe in the Sanremo roe Handbook.39 It is presumably also supported by those who, for instance, consider the isaf Tactical Directives on the avoidance of civilian casualties (also known as the civcas Directives) to be a form of roe.40 However, the wide definition seems impracticable. Depending on whether roe are legally binding orders or not (see below), it may also be at risk of offending the principle of legality: legally binding orders ought to be clear and ascertainable. If the roe are legally binding but nearly impossible to locate or get a complete overview over, it would seem unreasonable to sanction violations of those roe.
Another frequently reported problem created by using the term roe in an imprecise manner is that operators and JAs [Judge Advocates] reported frustration over having to search through voluminous material to find all of the “applicable roe”. Certainly, if one applies a broad definition of roe, which far exceeds that contemplated by the doctrinal definition of roe, to include special instructions, fire control measures, tactics, techniques and procedures, and so on, then there literally is no end to the perpetual hunt for roe.41
Operationally, the clarity provided by a narrow definition of what roe are and where they can be found is beneficial both for the Commander and the troops. It ensures the necessary predictability of how troops will act, on the one side, and what is expected of them on the other. If the roe are legally binding on the forces, the principle of legality makes such predictability essential. However, as will be explained below, roe are fairly rigid and therefore can be difficult and time-consuming to change. Furthermore, in the context of nato, roe authorisation requires consensus among all States, which is more likely to be achieved if the details are left to be established elsewhere, in documents which are owned by the Commander rather than the North Atlantic Council. As a result, there is a need for additional ways of communicating how the roe should be interpreted, both in light of changing mission requirements and threats,42 and to enable further detail in the use of force direction. This additional guidance may be provided through documents such as Tactical Directives, and Standing Operating Procedures, even if they are not referred to as roe.
A narrow definition of roe does not necessarily exclude the existence of these documents otherwise included in a wider definition of roe, but it does exclude them from having the formal status as roe. Instead, they should be viewed as “complementary and separate”.43 By providing the more detailed instructions in other documents, the necessary information on the use of force and other provocative acts may be communicated without making the roe themselves too detailed and voluminous. The information would still be there, but this distinction ensures a form of hierarchy among documents dealing with the use of force and other provocative acts, with roe having a superior standing.44 As a result, the roe would be the first place to look for information on what force or provocative acts may be used, and any additional documents ought to comply with the roe (i.e., in the narrow sense), in the way that regulations have to comply with existing laws, for instance. Furthermore, as will be discussed below (in Section 2.2.2), although most countries consider roe to be legally binding military orders, the legal status of other instruments is less clear.
By separating roe and other guidance on the use of force and provocative acts, it becomes possible to provide such additional guidance without it amounting to legally binding obligations. It may instead be founded on policy only, and may for instance be intended to remind the forces of the purpose of the mission rather than to change the conditions under which they operate by introducing additional legally binding restraints. It also enables States to distinguish between practice driven by policy only and practice influenced by an opinio juris in the context of customary law development.
A consequence of this distinction between legally binding roe and other, non-binding, documents should be an increased awareness of whether new guidance on the use of force and other provocative acts is intended to be legally binding or not, in order to issue the guidance in the correct form. For States who view all instructions as legally binding orders, this hierarchy may still serve a useful role. Documents such as sops and Tactical Directives are often extensive and may contain a combination of direction and guidance not clearly distinguished from the other.45 The roe could then provide clearer instructions on what is expected and even serve as a useful tool for interpreting the other instruments. Preferably, the situation should have been possible to sum up by the following explanation offered by an isaf Commander to his troops: “The r.o.e are the can and cannot. (…) They are the rules of the game. The Tactical Directive covers should and should not”.46
Admittedly, although such a distinction would be preferable, the distinction is not that clear in practice. At least parts of a tactical directive should be perceived as orders and hence binding, and because the remainder will be a reflection of the Commander’s intent, the forces may not choose to disregard it.47 As Boddens Hosang explains, roe “are an integral and essential part in a complex system, in which each of the parts must interact and be applied in proper cohesion with the others for the system to function as designed”.48
2.2.1.4 Mission Accomplishment roe versus Self-Defence roe
Though not reflected in the various definitions of roe, a distinction is commonly made between self-defence roe and mission accomplishment roe.49 Mission accomplishment roe are “based on a detailed mission analysis, particularly an assessment of the threat environment, force protection requirements, and the extent to which coercive force will be needed to accomplish the mission.”50 Unlike self-defence roe, mission accomplishment roe will for instance establish guidelines for pre-planned attack.51 However, as nato roe do not regulate the use of force in self-defence, this distinction will not be employed in this book.52 nato roe are developed to enable a unified approach to the use of force in order to accomplish the common mission. As such, all nato roe are mission accomplishment roe.
Before the MC 362 was developed, that is, during the Cold War, attempts were made to regulate the use of force in self-defence in nato roe. However, limitations imposed on the use of force in response to imminent attacks in particular were viewed as a limitation on the national interpretation of self-defence, and was thus a cause of great frustration for the United States, amongst others. As a result, when the MC 362 and later the MC 362/1 were developed, they did not include roe on self-defence. Today, nato emphasises that it has no authority to enforce a common legal position for all member states. Instead, the focus is on operational effectiveness, and an expectation that all member states operate within their respective applicable legal regimes.53 As the scope of the right of self-defence differs among the troop contributing nations, this is left as a national matter.54
2.2.1.5 Mission Specific roe versus Standing roe
Another way to distinguish roe is to differentiate between mission specific roe and standing roe. Mission specific roe are tailored to a specific operation which may cover both armed conflicts and other operations where there is a need to control the use of force. For instance, nato develops new roe for all its operations. By contrast, standing roe are in existence at any time, and will apply to all operations, subject to any additional guidance being issued for specific operations. Because standing roe presume a form of standing force, they are commonly national and provide national policies and procedures for the use of force by the respective national forces. The best known examples of this form of roe are the Standing Rules of Engagement (sroe)/Standing rules for the use of force (sruf) for U.S. Forces and the predecessor U.S. Peacetime roe (proe).55 The U.S. roe system has clearly influenced the use of roe both by other States and by international organisations.56
Because nato has both standing multinational groups and has recently become more involved in activities which do not amount to operations with a corresponding Operational Plan (oplan)57 and roe,58 it would be useful for nato to have the possibility of using standing roe. However, this is currently not part of the nato roe system (MC 362/1). Instead, standing multinational groups such as Quick Reaction Forces (qrf) or Very high readiness Joint Task Force (vjtf) may have pre-approved roe which resemble standing roe, but are dormant mission specific roe than standing roe.59 These ensure that the forces will have roe available when needed, despite their rapid deployment.
Activities not involving operations include for instance maritime interdiction carried out by nato Standing Naval Forces in order to help deal with the refugee and migrant crisis in the Aegean Sea.60 Because of the nature of the activities, nato’s operational planning procedures61 are not best suited for planning the operation. However, roe are an integral part of this process and the resulting oplan, which means that the current procedures do not envisage roe outside of operations. Still, the forces involved will still need guidance on the use of force and other provocative acts. Standing nato roe would therefore be useful, but has currently not been developed.62 One of the main challenges with establishing a form of ‘nato Standing roe’ would be to identify a standing legal basis for the use of force applicable to all nato States. nato activities, as opposed to operations, will commonly involve peacetime tasks rather than participation in an armed conflict. Because nato roe cannot be based on self-defence, alternative peacetime legal bases for the use of force would be required. The use of force by military forces during peacetime, beyond self-defence, is a complex topic. It may therefore be difficult for States, through the nac, to come to an agreement on such roe.63 The alternative would be to only include roe regulating the use of provocative measures not including force, such as physical obstruction, passing of warnings, exercising in the vicinity of a potential enemy, or conducting simulated attacks. The use of force would then only be authorised in cases of self-defence.
2.2.1.6 Restrictive versus Permissive Approaches to roe
Initially, the use of nato roe was intended to differ for operations below and above the threshold of an armed conflict.64 roe for peace operations would be restrictive in nature, in that Commanders would only have the authority to carry out actions provided for by roe, apart, of course, from self-defence. During armed conflict, on the other hand, Commanders would be able to do anything permitted by law, unless prohibited or limited by roe – a more permissive approach. In other words, roe were intended to function differently as a Command and Control tool in these two types of situations, and the interpretation of roe would differ depending on the operation. As will be explained below in Section 2.2.1.8, this distinction is no longer as clear, and all use of force and provocative acts are nato forces are authorised to apply will be expected to be expressly authorised by roe (with the exception of force used in self-defence).65
It should be noted, however, that terms permissive and restrictive commonly (and confusingly) are used in two different, though interrelated manners when describing roe. In the abovementioned context, they are employed to describe the difference between roe providing the sole authority for the use of force and other provocative acts, or simply imposing certain restrictions on the amount of force permitted by law. However, the terms restrictive and permissive are also used to describe the degree of political control over the use of force and other provocative acts, and how much room for manoeuvre the roe provide a Commander and the forces.66 For instance, the U.S. Army Operational Law Handbook explains that “[i]n contrast with U.S. roe, which are generally considered permissive, nato roe may be considered by some to be more restrictive in nature. However, nato roe are always mission specific, and thus not by definition or default more restrictive that U.S. roe”.67
While the former use of the terms refers to the overall approach to roe, the latter is a description or critique of the nature of the existing roe. As a result, roe of both the permissive (peacetime) and restrictive (armed conflict) approaches may be assessed as restrictive or permissive in the second meaning of the terms, depending on the perspective and expectations of whoever is making the assessment. When the terms restrictive or permissive are used in this book, it will therefore be made clear which of these types is being referred to. The issue of how existing roe have been perceived is further discussed in Section 2.4.1.
2.2.1.7 nato roe as the Sole Authority for the Use of Force or Other Provocative Acts
nato documents make reference to the view that with the exception of self-defence, all use of force and other provocative acts must be authorised by roe. As a result, nato roe are the ‘sole authority’ for the use of force or other provocative acts during nato operations.68 This has been the cause of some confusion, for three reasons. First, as will be explained in Section 2.2.1.8, the ‘sole authority’ language is only used in the MC 362/1 in relation to peacetime operations.69 Second, certain States have applied national roe in addition to the mission specific nato roe, and the claim that nato roe provide the sole authority for the use of force and other provocative acts may be viewed as denying States the right to apply such national roe. Although the existence of a parallel system of roe may be confusing and thus undesirable, their application is not limited by nato roe being the sole authority for the use of force and other provocative acts. Provided that the alternative national roe are only applied to operations carried out outside the nato chain of command, as part of national operations, the use of such force or other provocative acts is not considered to have taken place as part of a nato operation.
The third confusion concerning the ‘sole authority’ language is whether it implies that the roe are the legal basis (‘authority’) for the use of force and other provocative acts. As will be explained further in Section 2.4 below, roe are drafted in accordance with the applicable law, but are also intended to reflect operational and political considerations. They are intended to be internal procedures, not international law creation.70 The use of force or other provocative acts must always have a legal basis; the function of the roe is to communicate to the forces what their Commander(s) authorise them to do, within the parameters set by the nac and by applicable law. Only the use of force in self-defence is not affected by nato roe, as this is, as explained above,71 regulated by the respective troop-contributing nations’ domestic legislation.
2.2.1.8 Peacetime Operations (and Operations Prior to the Commencement of an Armed Conflict) versus Armed Conflict Operations
As mentioned above in Section 2.2.1.5, it was initially intended that nato roe would be applied differently during operations below or above the threshold of armed conflict (as well as, of course, applying different roe). However, over the past fifteen years there has been a change in the way nato applies roe to armed conflict. Rather than differentiating between types of operations, nato has applied the more restrictive approach, previously reserved for peacetime operations, to all operations when drafting roe.72 This means that nato roe are primarily formulated as authorisations, and are, with the exception of self-defence, the sole authority for the use of force and other provocative acts in nato operations.73 The isaf operation in Afghanistan and operation Unified Protector in Libya are examples of this approach to roe.74 In practical terms, this means that if there is no nato roe permitting the use of force or an otherwise provocative act, and self-defence does not apply, that act cannot be undertaken.
It should be stressed, however, that this harmonisation of nato roe for operations below and above the threshold of armed conflict only applies to how roe are drafted and thus used as a command and control tool. It does not harmonise the approach to when, how, how much and against whom force or provocative acts may be used. For instance, the roe authorising attack on the basis of the status of a person or object as a lawful target would only be available for operations entailing participation in an armed conflict. Furthermore, the degree of detail in the roe and hence the degree of detailed command and control applied in a given operation will depend on the facts, including but not limited to the classification of the situation as an iac or niac. For instance, the roe for an nato Article 575 operation are likely to be more robust than roe for a so-called ‘war of choice’ because it is imperative that an Article 5 operation succeed. This may be achieved either by having roe authorisations formulated in a wider manner, or alternatively, the originally intended methodology for armed conflict operations may be invoked, whereby the use of lawful force is authorised unless prohibited or restricted by the roe. At the same time, it may also be that the roe are even more detailed, in order to prevent a conflict in a nato State from escalating into a full-blown war. Furthermore, although there will be stronger incentives to succeed in an Article 5 operation, the acceptance of risk to the civilian population will not necessarily be any greater than operations such as isaf and oup.
There is no official explanation for this shift in nato’s roe methodology. A likely cause, however, is the increased desire for political and operational control over the use of armed force. This desire emanates both from political, strategic and operational levels of command as well as from civil society which appears to have an increasingly lower tolerance for errors made by military forces. It is not considered sufficient to permit military forces to do anything not prohibited by the law of armed conflict, and only impose certain limitations on this relatively wide room for manoeuvre in the form of roe prohibitions. It significantly reduces the scope for using roe as a tool for political control of the operation, and from the strategic level perspective, this is the primary function of roe. Furthermore, it would require all military forces to be experts of all applicable loac rules, and also to know and understand the intentions of higher echelon well enough to act within the parameters of what they expect of their subordinate troops. The alternative and currently favoured approach in nato is therefore to use roe to define in more detail the parameters within which nato forces may operate. This way, the decision on when, where, how and against whom force may be used, and who may authorise the use of such force, is not left for anyone to make.
The harmonisation of roe methodology for all operations has the added value of making the roe less complex and hence easier to train and apply. It is simply too complicated to have two separate approaches to the use of roe within the same system, especially when the situation in an operation may change from peace to armed conflict and vice versa, thereby requiring a change in roe methodology as well. It also enables the roe to be adapted to differing situations within the same operation. There may, for instance, be a full blown armed conflict in one area of the operation and hybrid warfare with less clear attribution to the opposing forces in another area.
Finally, upholding a distinction in the roe methodology between operations involving participation in an armed conflict and those that do not, would require nato and the nac to make a determination of whether a situation amounts to an armed conflict or not. However, nato member States will not necessarily agree on this determination, as the situation in Afghanistan illustrated. For instance, Germany would not classify their contribution as participation in an armed conflict until after the 2009 Kunduz airstrike alleged to have killed several civilians.76 Although the Geneva Conventions make it clear that the classification of a situation as an armed conflict or not should be based on the facts only,77 it will in practice be as much a political as a legal determination. It will therefore not make sense to have a roe system that depends on the nac being able to reach consensus on such a complex issue. The appropriate determination to be made in the nac is whether an Article 5 situation exists, and how robust roe an operation should be authorised to have. States do not need to agree on their respective political and legal justifications for coming to such an agreement.
2.2.1.9 Interpretation of nato roe for the Purposes of This Book
Although some preliminary conclusions may be drawn on the nature and form of roe, one of them must be that there is no harmonised understanding of roe within nato. However, for the sake of this book, roe will be viewed as orders that regulate when, where, what and against whom force or other acts which may be construed as provocative may be used. Furthermore, a narrow interpretation will be applied, in that roe are a set of orders in the form of roe serial messages, expressly authorising or prohibiting certain acts. Other documents, such as sops and Tactical Directives, are considered to be supplemental documents setting out how the roe should be applied. Finally, roe will be viewed as providing the only authority for use of force and other provocative acts during nato operations (except for self-defence situations), both for operations below and above the threshold of armed conflict.
2.2.2 The Binding Force of nato roe
The legal analysis of the use of force authorised by roe begs the question of what roe are, legally speaking. There are particularly two aspects that are relevant here: what is the consequence for individuals or States who fail to respect or comply with the roe for a mission? And what is the relationship between roe and other operational documents?
Considering that there is no universally accepted precise definition of roe, but rather a common understanding what roe generally entail, it is perhaps not surprising that there is no universal approach to the question of the binding force of roe either, neither in relation to national nor international law. The question of the legal status or binding force of roe may affect how States and individuals will relate to roe, both in relation to interpretation and application, and especially with regard to compliance and the possibility of sanctioning violations. This will in turn affect the effectiveness of roe as a command and control tool. The following section will therefore examine the legal status of roe in international and national law.
2.2.2.1 Obligations on the State
The first question is whether nato roe give rise to any obligations on behalf of the States. nato roe require consensus among the 29 Member States in the nac in order to be authorised.78 As such, the roe for an operation amount to a form of inter-State agreement. The extent to which this agreement is binding on the States depend on whether it becomes a legally binding agreement or is merely an internal document which all nato Members States are expected to comply with due to their nato membership.
Agreements creating legal obligations under international law are commonly referred to as treaties. Treaties primarily bind States, not persons. States party to the treaty would be obliged to ensure compliance by persons acting on behalf of the State, such as members of their respective Armed Forces, respect it.79 As explained in Section 1.4, the definition of a treaty is found in the vclt, which in relation to international organisations applies to both the constituent instrument of the organisation and any treaty adopted within the organisation.80 According to Article 2(1)(a), a treaty is “an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation”.81
In its Commentary on the final Draft Articles of the vclt, the International Law Committee has explained that the requirement ‘governed by international law’ embraces an “intention to create obligations under international law”.82 This requirement of intention was further elaborated on by the International Court of Justice in the Aegean Sea Continental Shelf case in 1978. The Court held that the parties to a ‘Communiqué’ had not intended to create a treaty to submit to the jurisdiction of the Court.83 Thus, as Aust concludes, “If there is no such intention [to create obligations under international law], the instrument will not be a treaty”.84 Such reliance on the intention of the parties has been criticised by Klabbers, among others, in relation to inter-State agreements, for being “at odds with international practice”.85 However, a distinction should be made between inter-State agreements and the issue at hand here, namely documents created in order to enable cooperation and interoperability within nato.
Rather than creating agreements to be relied upon in inter-State relations in general, nato Member States consent to “standards and rules of general applicability [to be] adopted by subsidiary bodies”.86 Most of the documents produced by or approved by the nac, such as roe, are at least as much politics and operational considerations as law, and are intended to change as operations evolve and in some cases be replaced for each new operation. It is therefore unlikely that the purpose or intention of the nato Member States is to create obligations under international law which if violated would be subject to sanctions, for instance by being subjected to the jurisdiction of the International Court of Justice. It is actually more likely that the intention of the States is the contrary: namely, to create documents which are not legally binding.
Similarly, documents like roe are unlikely to amount to soft law. Soft law may be defined as “international instruments that their makers recognise are not treaties, even if they employ imperative language such as ‘shall’, but have as their purpose the promulgation of principles or rules (albeit not legally binding) that the authors of the text hope will become of general or universal application”.87 Those developing roe will, however, have no intention of them becoming ‘general or universal’; they are intended to function as political constraints on the use of force and a tool for command and control. In fact, most nato documents are either classified or subject to limited release, and are thus of limited value for influencing States that are not members of nato or part of the operation.
Consequently, it seems more appropriate to state that nato regulations in general, such as in the form of doctrines, rules and policies, are internal documents or administrative agreements for nato, applicable to State forces and personnel while involved in nato operations.88 Regulations approved by consensus by the nac, or by a senior committee which nac has delegated this authority to, may according to nato be normative in the sense that they are binding upon all of nato.89 There is no set terminology used by nato to signify that a document is normative, and an assessment must thus be made based on the content and purpose of the document. This is likely to be the case with roe. As such they are binding on the organisation because they are created in order to carry out the legally binding aspects of the 1949 North Atlantic Treaty (a.k.a. the Washington treaty),90 but they do not amount to a treaty or other legally binding agreements. In other words, any legal obligations arise from the North Atlantic Treaty, and documents such as roe are merely produced as an internal mechanism to fulfil these legal obligations and to attain the purposes of the organisation. The fact that States do not require their respective domestic legislative bodies to consider the agreements supports this conclusion. According to Moritz, it may be assumed that “a member-state, as a rule, will only give consent where it is certain that the decision will not be contrary to the national law or that a necessary amendment of the national law will meet no difficulties”.91 Although this is generally correct, as will be explained in Section 2.4.2, nato States do not actually ‘give consent’. Instead they will be perceived to consent unless they announce objections by ‘breaking silence’, thereby potentially preventing the decision to be reached. In cases where States only object to their own involvement, they may allow the decision to be made, but caveat its application to its own forces.92
In order to avoid arbitrariness, even internal documents should be interpreted in accordance with general rules of interpretation, at least when there are no statements to the contrary.93 This means that they should be interpreted primarily on the basis of the actual text; read in light of the ordinary meaning of the terms, as applied in nato operations and doctrine; in good faith; and keeping the object and purpose of the specific document in mind.94 The nac Initiating Directive for the operation, the Political Policy Statement in the implemented roe, and the Commander’s Decision and Guidance for the operation are examples of relevant sources for ascertaining the object and purpose of the roe. Because nac’s intention with roe is to provide political constraints on the use of force, it is important to be restrictive in the interpretation, thereby ensuring compliance.
If there is a disagreement over the interpretation or application of the roe, nato’s internal procedures do not dictate any general solution to such a problem. In practice, it will be a matter for the Commander for the given operation to handle, for instance by issuing clarification and further guidance in orders or directives. As mentioned above, States are, however, free to impose additional restrictions on the use of their respective forces in the form of caveats.95 If the disagreement has severe consequences, the nac would be expected to consult on the issue.
The conclusion must therefore be that roe does not impose legal obligations on States; however, States are nonetheless expected to respect and comply with the nac approved roe. Failure by member States to respect nac decisions could potentially undermine nato as an organisation, which should hopefully provide the necessary incentives for compliance.
Before moving on to look at how roe are dealt with in national law, two related questions of international law will be considered. First, the fact that nato roe do not create legal rights or obligations further supports the clarification presented in Section 2.2.1.7 on the phrase “roe authorise”. Although the term ‘authorise’ may seem to have certain legal connotations, it should merely be understood to mean that the Commander permits the (presumably lawful) actions to be undertaken.96 This is why nato descriptions of roe refer to political constraints on the otherwise lawful use of force.97
The second issue is whether roe represent State practice and thus development of customary international law.98 Based on the above it should be concluded that States do not appear to consider the roe themselves to be legally binding, and as a result, the element of opinio juris is lacking. However, the roe may nonetheless affect customary law development, or at least interpretation of current rules, in so far as it provides an indication of what the States consider to be lawful. As has been pointed out, roe do not amount to an independent legal basis for use of force or other provocative acts, but must comply with existing law. The fact that the use of force in a given set of circumstances is authorised in a roe, signifies therefore that States consider such force to be lawful. If the applicable law is unclear, the roe will provide a useful example of interpretation of that law or of customary law.
For instance, during armed conflict, the use of force in accordance with roe must only be directed at persons considered to be lawful targets. As mentioned, nato roe do not regulate the use of force in self-defence. Therefore, if the operation takes place in a niac, for instance, the roe must only permit the use of force against persons who take direct part in hostilities,99 whether as part of an organised armed group or independently.100 For instance, this entails that nato roe authorising attack on persons carrying out a ‘hostile act (not constituting actual attack)’ or demonstrating ‘hostile intent (not constituting imminent attack)’ may be viewed as State practice on who is lawful targets under loac, especially the authority provided by the notion of ‘direct participation in hostilities’.101 However, although State practice during military operations provide important contributions to the evolution of international law, their ability to influence other States is limited by the tendency to make operational orders and procedures classified.
2.2.2.2 The Status of roe in National Law
As mentioned above, the binding force of roe and the possibility for sanctioning violations of roe will arguably encourage compliance with them and, as a result, affect the effectiveness of roe as a command and control tool. As with other roe related issues, however, national approaches to whether roe are legally binding or not, vary greatly. According to Fournier, “some nations consider roe to be instructions, directives or guidance where other treats [sic] them as valid order to be obeyed and respected”.102 This is supported by the results of a survey undertaken by the International Society of Military Law and the Laws of War in 2006, in preparation for the 17th International Congress on “Rule of law in peace operations”.103 The question of whether roe are legally binding in many countries is related to the question of whether roe are binding military orders. Therefore, the two following questions of the questionnaire are of relevance here: “To what extent does your country consider roe to be legally binding on the forces?” and “Are roe considered to be orders?”104 Unfortunately, not all nato Member States responded to the questionnaire, but the report still provides useful insight into how the questions are dealt with nationally.
Since roe are by their definition guidelines for the use of force, and Croatian Armed Forces members act in accordance with laws, regulations and orders, the eventual application of roe cards would need to be regulated by means of the appropriate state authority which would issue a regulation, and also by an order which would be issued, by the military Chain of command.106
A plausible cause for the different approaches taken to the character of roe may be the divergence in national definitions of military orders. For instance, it may be the case that military orders are defined in such a way that they cannot encompass roe, or that roe may only be regulated by domestic legislation if it is expressly stated that roe are viewed as a form of military orders. It may be that there is an exhaustive list of how military orders are to be communicated, and roe are not listed due to its relatively recent introduction to nato. For some States, particularly those who have joined nato more recently, their position may also be influenced by the wording in the nato definition (“directives” rather than “orders”).
As military orders are normally legally binding upon troops, such as through military penal codes or disciplinary laws, it would be expected that all States who consider roe to be orders to also answer that they are legally binding, and possibly vice versa: that States who do not consider roe to be orders, would not consider them to be legally binding. This is not the case, however. Two of the countries which do not consider roe to be orders, namely Greece and Latvia, still see them as binding upon the troops. However, they do not provide any explanation for how the roe are legally binding.107 Belgium and Croatia, on the other hand, state that roe may become legally binding when they are incorporated into superior orders.108 Presumably, this means that roe are not legally binding, but the military orders, requiring compliance with the roe, are.109
Despite the differences in approaches to roe among nato States, the practical outcome is not so divergent. Whether roe are orders or an order is given to comply with roe, the result is that the roe are binding upon the troops, and any violation may be subject to disciplinary or penal sanctions, even when the act does not amount to a crime in itself. As will be seen below when dealing with roe as a tool for command and control, this is important for the effectiveness of roe.110
2.3 The History of Mission-Specific Rules of Engagement
A comprehensive understanding of roe requires an understanding of the historic origins of the concept.111 Rather than providing an extensive overview, however, the following will focus on the aspects most relevant for this book.112 As a result of the focus on (mission-specific) nato roe and armed conflict, classic examples of roe challenges, such as the 1983 attack on a U.S. Marine Corps compound in Beirut, the Iraqi attack on uss Stark in 1987 or the shoot down of the Iranian Air Flight 655 by the uss Vincennes in 1988, will not be dealt with. Although important and interesting cases, the roe applicable to these cases were standing roe that regulated the use of force in self-defence.113
From now on all enemies on so-called commando missions in Europe or Africa challenged by German troops, even if they are to all appearance soldiers in uniform or demolition troops, whether armed or unarmed, in battle or in flight, are to be slaughtered to the last man. (…) Even if these individuals, when found, should apparently be prepared to give themselves up, no pardon is to be granted them on principle.114
Unlike the order from Bunker Hill, it is a general rule for the use of force, and not merely an independent order for the use force in a concrete situation.
Similarly, it is important not to confuse roe with expressions of the law of war or armed conflict (loac). Although legal rules in some cases may be considered so important that they are imported into the roe, this is not usually the case. As will be further explained below, roe should also reflect operational and political considerations, and in the case of a conflict of interest between the two, provide guidance on how they should be balanced. Thus, statements such as ‘do not murder prisoners of war’ or ‘looting is prohibited’ should generally not be viewed as roe. 115
[w]ith the advent of oar and sail, effective central control of a military asset by the sending government was lost once a ship got underway from port. It was incumbent upon the commanding officer to conduct the mission pursuant to the general guidance of the government. Virtually alone until the ship reached the next friendly port, or until the ship encountered another friendly vessel that could deliver news or orders, the commanding officer operated within broad parameters or rules issues by the leadership.116
In its modern form, roe as a concept and term was used for the first time in maritime and air operations in the 1950s.117 More specifically, it is argued that the first use of modern concept of roe, although not yet referred to as such, was the 1948 United States Navy Regulations with Article 0614, “Use of Force Against a Friendly State”.118 The first time modern mission-specific roe were used, appears to be during the 1950 air campaign over North Korea when “General MacArthur received orders from Washington that American bomber aircraft were neither to enter Chinese air space nor destroy the Suiho Dam on the North Korean side of the Yalu River.”119
The term roe itself appears to originate from a set of ‘Intercept and Engagement Instructions’ issued by the U.S. Joint Chiefs of Staff (U.S. jcs) on 23 November 1954.120 The instructions were issued on the basis of several dogfights between American and Soviet aircraft, resulting in the downing of least three American and three Soviet aircraft, and were referred to as “Rules of Engagement” by Air Force and Navy staffers. At the same time, it also made its way into nato doctrines, as illustrated by a 1957 report on the suggested draft for “Rules for Engagement of Unidentified Aircrafts By nato Fighters in Peacetime”.121 roe was formally adopted by the U.S. jcs in 1958,122 and was further developed during subsequent operations. The peacekeeping operations in the Dominican Republic 1965–66 is said to have “helped make the term “roe” familiar to American soldiers, who assimilated it into their vocabulary as a curse word” because of the restraints they imposed.123
I am ashamed of my country for having had people who would have allowed such restrictions to have been placed upon men who were trained to fight, men who were trained to make decisions. … and men who were risking their lives. … I pray. … such foolish restrictions never be formed again and applied to our troops.128
geographical limits of sea [Southeast Asia], territorial airspace, territorial seas, and international seas and airspace; definitions of friendly forces, hostile forces, hostile acts, hostile aircraft, immediate pursuit, and hostile vessels; rules governing what could be attacked by United States aircraft, under what conditions immediate pursuit could be conducted, how declarations of a “hostile” should be handled, and the conditions of self-defense.129
prohibitions against striking locks, dams, hydropower plants, fishing boats, houseboats, and naval craft in certain areas; prohibitions against strikes in certain defined areas such as the Chinese Communist (ChiCom) buffer zone or the Hanoi/Haiphong restricted areas; conditions under which targets might be struck, such as validation requirements, when facs [Forward Air Controllers] were required, distances from motorable roads.130
Finally, the Operating Rules concerned the use of Forward Air Controllers, the return of ground fire, the use of the AGM-45 (shrike) missile, restrictions on mine-type munitions, and the requirements for navigational position determination. 131 According to a U.S. Air Force report, “[a]lthough, in theory, these three types of rules were distinct, in practice, they were almost always referred to collectively as ‘Rules of Engagement’”. 132
The roe for the Vietnam War, as exemplified by those for Rolling Thunder, were considered so detailed and impracticable that it in fact became impossible to achieve the military objectives. The involvement of political leadership in the detailed running of the operations, such as the White House requirement for visual identification of targets,133 has been criticised for being the cause of the failures of the operation. Hays Parks, for instance, has contended that “Rolling Thunder was one of the most constrained military campaigns in history. The restrictions imposed by this nation’s civilian leaders were not based on the law of war but on an obvious ignorance of the law – to the detriment of those sent forth to battle”.134
The resulting frustration with and distrust in roe most likely influenced the further development of the use of roe so that roe for subsequent operations appear to have been more robust and flexible. An example of such robust roe may be found in the Iran-Iraq war (1980–1988), partly referred to as the ‘Tanker War’. The United States Navy were involved in escorting Kuwaiti tankers through the area when the uss Samuel B. Roberts hit a mine laid by Iran. As a result, Operation Praying Mantis was initiated in April 1988, and President Reagan approved roe that permitted U.S. forces to attack two Iranian oil platforms and to seek out and engage Iranian patrol frigates.135 The robustness of these roe is likely to also have been influenced by the 1987 missile attack by Iraqi forces on the uss Stark, killing thirty seven crew U.S. Navy personnel. The incident is commonly used as an example of roe failure.136
Another example of more robust roe may be found in Operation Desert Storm (1990–1991), known as the First Gulf War. Here, the political and policy constraints on the use of force are said to have taken “a backseat to the clear military objectives of the operations, the most important of which was reversing Iraq’s invasion of Kuwait”.137 According to United States Air Force officer Lt Col Humphries, “[i]n the Persian Gulf, American political leaders embraced and heeded these lessons; they permitted their war fighters to conduct combat operations within the law of armed conflict without tying their hands with constraints. This, in turn, maximized the effectiveness of coalition air power”.138 In fact, Humphries goes so far as to argue that “[t]he Persian Gulf rules were different from those in Vietnam because they were about as broad as they could be”.139 One of the ways this was achieved was by allowing those who had to execute the roe to assist in their development. For instance, rather than the roe and strategic target lists being dictated by the White House, these were prepared by the U.S. Central Command Commander together with his war plan.140 Furthermore, the involvement of Central Command Air Forces (centaf) judge advocates in the development of the roe is said to have “ensured that the rules were no more restrictive than was required by the law of armed conflict and collateral limitations”.141
As the historic examples considered above indicate, it is difficult to strike the right balance between the political and operational considerations when formulating roe for an operation. This remains a challenge for current operations as well. As will be explained below, both overly restrictive and overly permissive roe, in the sense that there arguably is too much or too little political control, are problematic. Perhaps not surprisingly, most operations are criticised for having either overly restrictive or permissive roe, or both, depending on the background of the commentator.142 Still, roe have remained one of the main tools for controlling the use of force and other provocative acts, both during peace operations and operations involving participation in armed conflicts. The use of mission specific roe has subsequently been refined through more recent operations such as the Iraq war or Second Gulf War, the war in Afghanistan and more recently the nato operation in Libya.
2.4 roe Development
2.4.1 Law, Politics and Operational Considerations
In addition to understanding where roe come from, understanding why and how roe are developed is crucial to better comprehend what they are and how they function. The purpose of roe, as previously alluded to, is to impose political constraints on the otherwise lawful use of force and other provocative acts, and to enable operational control over the use of force. According to Schmitt, “First, and most fundamentally, roe are the means by which the National Command Authorities (nca) (or comparable authority in other countries) express their intent as to how force will and will not be used to achieve policy objectives”.143 For nato, the comparable authority will be the North Atlantic Council and the Military Committee. For military forces participating in the operation, the roe are more likely perceived as having an “inherently military operational nature”,144 the primary purpose being “to control the level of violence or confrontation in the area of operations”.145 Regardless of which purpose is considered more important, effective roe needs to strike the right balance between the political and operational considerations, within the parameters set by applicable law.146
The political or policy influence on the development of roe seeks to ensure that the political objectives of the mission are achieved. The roe help ensure that the actions of the Commanders and their forces reflect the national and multinational policies and objectives for the mission.147 Margaret Thatcher, who was the civilian Commander in Chief for the British forces during the Falkland War, understood roe as “the means by which the politicians authorize the framework within which the military can be left to make the operational decisions”.148 In the context of nato, the roe are authorised by the nac which consists of the representatives of all the Member States. This secures the political control by all nato Member States of the roe. Operationally, the roe define the Commander’s room for action to use his or her forces to achieve the mission, as defined by the political interpretation of the mandate for the operation. In addition, roe enable the operational level Commanders to exert control over subordinate forces and their approach to mission accomplishment, prevent unwanted escalation, and enable force protection.149 From both the political and operational perspectives, roe are a useful tool to control the forces and ensure to encourage desirable actions and discourage undesirable ones.
whether or not Allies other participating States agree on the exact legal justification or explanation underlying them, is in principle of little interest to nato as an organization. Thus, rather than requiring adherence to a single common body of law, the Alliance’s expectation is that all States participating in a nato or nato-led operation will act lawfully within the legal framework applicable to them.151
As a result, States must independently assess whether any proposed roe are acceptable to their interpretation of applicable law. If not, and depending on the severity of the issue, they may refuse to consent to the roe being authorised, or they may impose restrictions on the use of their own forces by declaring that they will only participate in parts of the operation or participate subject to caveats reflecting their concerns.152 Because the roe are intended to prevent violations of applicable law, they also provide commanders through the entire military chain of command with a tool for reducing the risk of the forces under their command carrying out unlawful acts for which they may be held criminally liable under the principle of superior responsibility.153
Rules of engagement (…) are designed to balance two competing requirements: the need to use force effectively to achieve the objective of an offensive or defensive mission, and the desire not to use force in unnecessary circumstances or in an excessively aggressive manner.155
While the law is relatively constant,156 the political and operational considerations to be balanced will be context dependent. As a result, the difference between roe for two different operations, both involving participation in an armed conflict,157 is therefore primarily caused by the different political and operational context and purpose of the operation.
Unless the roe are worded identically to the law, the result of applying operational and political considerations must be that the roe become more limited or restrictive than what the law permits, thereby imposing political and operational restraints on otherwise lawful use of force and other provocative acts.158
The ideal roe are those that are sufficiently flexible to be able to “balance the legitimate need for top-level guidance on appropriate action with the necessity for field-level judgements about specific conditions, threats, and opportunities”.159 Ideals, however, are notoriously hard to achieve. Furthermore, as the terms ‘appropriate’ and ‘necessary’ conveys, there is no objective test for where the balance should be struck, and where subjective assessments have to be made, there is a potential for disagreement. This is particularly true for people with different backgrounds and priorities, such as politicians and officers; their perspectives will be influenced by who they are and what they do. Where the former may be concerned with national and international perception, the latter are more focused on getting the job done. Though both categories will influence the development of the roe, they may have a very different view on what roe are needed and thus how appropriate the existing roe are. For instance, if a politician is asked whether a situation may be solved by the use of military force, he would consider whether diplomacy might be a more suitable alternative. A soldier, on the other hand, is more likely to reply that it would depend on whether they would be given the necessary resources and room for action to accomplish the mission.
While a slight imbalance is probably neither avoidable nor critical, serious problems may arise if the roe are either too restrictive or too permissive in the sense that there is either too detailed or too little political control of the use of force.160 Or as it also has been phrased: “The dilemma is one of action versus reaction”.161 Excessively restrictive roe will leave the Commander unable to effectively complete the mission and ensure force protection, potentially resulting in political failure and placing the men and women in the service of the State at unnecessary risk.162 Excessively permissive roe, on the other hand, may result in force being used “in a manner and degree that is deemed undesirable by national political authorities”.163 There is a real risk that the decisions made by so-called ‘strategic corporals’164 end up driving policy rather than enabling it. As States usually prefer to keep considerable political control over their military forces, there is more likelihood that the roe are too restrictive than too permissive. Unfortunately, the list of examples of operations that have suffered from unnecessarily restrictive roe is long, the archetypical example being the Vietnam War.165 The roe for Operation Rolling Thunder were later described by President George H.W. Bush as causing the forces to be “sent out to do a job with one hand tied behind their back”.166
[t]he Power despatching forces abroad must maintain a stricter posture of legality if its objectives are to be attained than one resisting pressure at home; and its rules of engagement must ensure tighter operational control and greater specification of the legal parameters of the operation.167
This is very much the case today as well, and the fact that mass media and the internet make detailed information of operations abroad available to anyone has arguably resulted in an increased desire for tighter political and operational control. People are confronted on a daily basis with pictures of suffering civilians from conflicts all over the world, and expect their authorities to do something to help. Coupled with increased awareness and expectations of modern technology, there is an increasing tendency to expect that military forces should not only be able to minimise the risk of mistakes being made, but that civilian losses could and thus should be avoided altogether.168 Many of the conflicts where the roe have been perceived as restrictive and even “simply patronizing in nature”169 have been complex in nature, where it has been difficult to distinguish the opposing forces from protected civilians. For instance, in isaf, the effort to enhance the protection of civilians resulted in both restrictive roe and a continued emphasis on the need to avoid collateral injury or damage to civilians beyond the requirements of the loac, amongst others in the so-called civcas Directives.170 According to counterinsurgency (coin) doctrines, such limitations are considered a prerequisite to mission effectiveness;171 however, the limitations imposed on the isaf forces’ ability to use force was criticised for placing them at higher risk.172 The emphasis on reducing civilian casualties was also influential during the 2011 Operation Unified Protector where only precision-guided munitions were permitted.173
Politicians generally prefer operations to be perceived as both legitimate and lawful. The emphasis on increased political control of the use of military force is therefore not surprising. As a result, the much-criticised practice during the Vietnam War whereby the Secretary of Defence, McNamara, personally approved not only targets but in some cases also “the aircraft, weapon loads, dates and times of strike, and routes of ingress to and egress from the target”,174 is not history, but in fact resembles the control the strategic level exercises over certain operations today. For instance, during the isaf mission, all targets to be nominated by German forces to a target list had to be approved by the national authorities.175 The U.S. applied a similar approach during Operation Enduring Freedom, where “pre-planned strikes, interdiction targets and time-sensitive targets all had to be approved by uscentcom”,176 and authorisation for a UK drone attack on UK citizens in Syria was given by the Secretary of State for Defence.177
That the political point of view should wholly cease to count on the outbreak of war is hardly conceivable unless pure hatred made all wars a struggle for life and death. In fact, as we have said, they are nothing but expressions of policy itself. Subordinating the political point of view to the military would be absurd, for it is policy that has created war. Policy is the guiding intelligence and war only the instrument, not vice versa. No other possibility exists, then, than to subordinate the military point of view to the political.178
The situation is neatly summarised by Bradd C. Hayes who stresses that “[t]he logic of conflict is the logic of politics rather than the logic of the military”.179 However, what the politicians probably are aware of, and concerned about, is the fact that even though war has as its purpose to serve a political end, “the nature of war is to serve itself”.180 These questions concerning the appropriate level of civilian control over the military relate to what has been referred to as the ‘civil-military problematique’, namely “the need to have an institution strong enough to protect civilians yet not so strong as to ignore civilian direction – in short, the problem of civilian delegation to and control of the military”.181 This has been the subject of extensive debate and research, most notably by Samuel Huntington and Morris Janowitz, and will not be dealt with further here.
Restrictive roe are not only the product of political desire for increased control, however. As Hayes explains, “the military chain of command’s desire to maintain control is every bit as strong as that of civilian leaders”.182 A further explanation for roe becoming too restrictive is therefore that they become more restrictive as they are implemented down through the chain of command. A Commander may never expand upon the roe given, but he may choose to limit them, unless this ability has been restricted by a superior Commander. For instance, a Commander may decide to introduce amplifications to roe to reduce the risk of them being interpreted in way that is not in compliance with the higher levels of Command’s intention, especially if the original roe are vague and thus open to misunderstandings.183 Commanders may also choose to restrict the roe due to a desire for further detailed control over any operation they may be held accountable for, which is basically any operation carried out by persons under their command. For instance, a Commander in charge of an area which the roe allow entry into, may order that entry into, for instance, a certain valley or village is prohibited because it may result in unwanted escalation of the conflict in that area. Similarly, Commanders may impose stricter requirements than what the roe and sops require for vetting sources of information used to determine whether a person or object is a lawful target.184
The perception of roe as too restrictive or too permissive is also likely to influence and be influenced by the approach taken to how detailed roe should be. This is related to the above discussion of degree of political control: more detailed roe enables more control, and vice versa, a desire for increased control may result in more detailed roe. As explained in Section 2.2.1.2, roe should not be ‘rudder orders’. roe are intended to “provide boundaries and guidance on the use of force”;185 they should not amount to neither “tactical control measures nor substitutes for the exercise of the commander’s military judgement”.186 Those supporting this interpretation of roe would presumably consider all roe containing such detail as overly restrictive.
However, not all view this level of detail inappropriate. Hays Parks, for instance, has criticised the description for not reflecting reality: “such a limited view of roe is not consistent with their proper use at all levels, and particularly at the operational level”.187 As an example, Parks points out that roe to the effect of “these targets will be attacked only with observed fire or guided munitions”188 are not uncommon, and he does not appear to consider such roe as inappropriately restrictive. Park’s criticism is supported by Sagan, who stresses that the civil authorities have a legitimate interest in ensuring that military operations serve the higher political interests, and that this includes control over the use of weapons.189 In other words, a certain level of detail should be expected, without it necessarily making the roe too restrictive.
[w]hile the political considerations and objectives are paramount, the political objectives will not be achieved unless the military considerations are properly addressed. If the roe are too restrictive, then the commander cannot accomplish the military objective and could potentially suffer unnecessary human and material losses. Either military failure or unnecessary losses could translate into political failure.191
2.4.2 nato roe Drafting
the question of applicable law will be addressed pragmatically, in the specifics of the oplan and the roe. What the planners prepare and saceur, through the Military Committee, presents for Council approval takes national positions into account, but in practical terms proposes specific rules and approaches for particular anticipated circumstances rather than offers conceptual views on the applicability of one or another legal doctrine or body of law.199
She goes on to explain that “[a]ny such differences are in any event likely to be relatively minor and inclined to being addressed at the level of implementation”.200 The differing legal obligations of nato States will therefore usually not affect the roe development.
Most of the suggested roe in MC 362/1 require tailoring to the situation, such as by designating the categories of persons that may be detained201 or defining the degree of force that may be permitted to be used in the respective situations. In addition, the MC 362/1 contains spare rules and series that may be developed if the existing roe are not sufficient, thereby enabling the doctrine to be applicable even to unforeseen roe. If there is a need to provide further information on a roe, a roe amplification (ampl) may be added, for instance stating the level of authority required for applying a roe.202
The roe form part of the Operational Plan (oplan) for the mission, as one of the annexes to the main plan, although the roe are developed in parallel to the remaining parts of the oplan and its other annexes.203 In order to know which roe are needed to accomplish what the Commander wants to do, the concept for the operation must be evolved and the development of the oplan must have begun. At the same time, the completion of the oplan depends on the approval of the roe. The successful integration of these two processes is therefore important for the effectiveness of the operation.204 Once the draft is produced, these draft or illustrative roe are discussed at various levels in nato and in different military and political working groups. The final version of the proposed roe (roe request, roereq) must be presented to the Military Committee205 for endorsement, before it is finally presented to the North Atlantic Council206 for authorisation (roe authorisation, roeauth).207
As previously mentioned, all decisions in the nac are made with consensus. nato has developed a ‘silence procedure’ as a means of reaching consensus. Rather than all representatives or States voting for a text, the text is circulated and will be adopted if no one objects to it or ‘breaks silence’. If silence is broken, the working group proposing the text will typically meet again to resolve the issues.208 No distinction is made between those nato Member States who are participating in the mission at hand and those who do not plan to do so.209 The nac decisions is informed by assessment and justification of saceur and shape for requesting the roe as well as the military advice from the Military Committee and the International Military Staff and the political advice from the International Staff. The roe that are authorised by the nac are then implemented (roe implementation, roeimpl) down through the chain of command in the form serial messages, that is, a list of coded one-line messages. At the lower levels, a distillation of relevant roe is commonly presented in the form of soldier’s cards or roe cards, special (air) instructions (spins) or maritime instructions. These are shorter summaries of the most relevant and important roe, tailored to the requirements of the respective tactical forces.210
Even though nato roe are formed on the basis of the consensus of all nato States, a State may choose to caveat a particular rule at any time.211 Caveats should preferably be notified during the planning phase so that they may be included in the oplan for the operation. In practice, they will be submitted to and published by shape,212 at the same time as the ‘Transfer of Authority’ (toa) of national forces to nato is executed.213 Importantly, caveats may only impose further limitations on the use of force and other provocative acts; they can never expand on what the nato roe permit. According to Fournier, there are four grounds for such caveats: 1) to ensure compliance with national law; 2) to ensure compliance with the State’s differing interpretation of or obligations regarding international law; 3) because the State interprets the UN mandate differently; or 4) to impose additional restrictions or limitations on the use of the State’s forces, such as geographical limitations or prohibitions on using certain ammunitions like rubber bullets or tear gas.214 For instance, there may be disagreements among the troop-contributing nations as to the legal classification of a situation (e.g. whether armed conflict or not, and if an armed conflict, the type) or the application of human rights law. Although caveats are difficult to avoid and are a useful mechanism to enable nac decisions in areas not all members States agree, they do create operational challenges in that they impose restrictions on the Commanders’ use of the troops made available to him. Too many caveats may thus make the contribution of the State in question considerably less effective, and extensive use of caveats has been much criticised.215 So-called ‘undeclared caveats’ are particularly problematic.216 These are national limitations on the use of forces that are only declared if the issue arises, which makes it impossible for the Commander to take into account in the planning of an operation.
There is a tendency to leave the development of roe to the lawyers, perhaps due to a misconception that roe are legal instruments. However, as Daniel P. O’Connell points out, “the drafting operation is likely to be successful only if there has been the requisite thinking in advance about the questions that could arise, including the tactical factors that enter into the processes of legal appraisal”.217 Thus, in order for the roe to best reflect the operational, political and legal considerations, the roe should be developed by a combination of operators, especially from the current and future operations branches (J-3/3–5), and subject matter experts such as legal advisers and political advisers, as well as representatives from J-2 (intelligence) and J-5 (future plans).218 As the J-3/J-5 is responsible for conducting and planning operations, it is natural that they are in charge of the roe.219 Perhaps in that way the following dire situation described by Hays Parks may be avoided: “By and large, roe produced by the most lawyer-heavy military in the world are cut-and-paste, copycat products lacking in original thought or analysis for current missions”.220 Legal adviser will, however, play an important role in interpreting the applicable roe and ensuring that they are applied in accordance with applicable law.
As mentioned above,221 it was originally intended for roe for operations below the threshold of armed conflict to be expressed as authorisations, while roe for armed conflict operations would be written as prohibitions or restrictions. However, current practice indicates that the roe for any operation are likely to consist of a combination of authorisations and prohibitions.222 For instance, a roe may state that ‘Use of minimum force to prevent interference with the freedom of movement of nato-led forces is authorised’, while another roe in the same roe pack may state that ‘Entry into State Bravo except for search and rescue purposes is prohibited’. Arguably, the requirement for a roe for all use of force (unless self-defence) makes the use of prohibiting roe redundant. However, it may still be necessary to use prohibiting roe where it is crucial that something is not done or where there are limited exceptions to the rule. For instance, as illustrated above on roe drafting, entry into a geographic area close to a neighbouring country may result in unwanted escalation and thus be prohibited. It may still be necessary to include an exception to allow for such entry for search and rescue purposes. In complex operations involving both traditional warfare and hybrid warfare, it may also be that there is a need to prohibit certain roe for certain geographical areas. Extensive use of prohibitions should, however, be avoided in order to prevent overly complex roe and misunderstandings. As Reilly explains, if a soldier sees an act being prohibited in one roe or soldier’s card, but do not see it in another, he may think the act is now allowed.223
Unless otherwise provided, Commanders at any level may decide to retain the power to authorise a roe.224 It may also be stipulated in a roe that the power to authorise the use of the roe in question is not to be delegated below a certain level of command. As a result, forces below that level of Command must ask for authorisation to use the retained roe. A retained roe may be released for a period of time, for a specific operation, or only when needed, thereby requiring the forces to contact the Commander in question when the need arises. Such release must be distinguished from delegation, whereby the authority to authorise the application of a roe is given to a subordinate command. The use of a retained roe may be authorised without delegating the release authority. If roe are retained, this must be taken into consideration when planning an operation, for instance in the development of the concept for the operation (set out in the conops) in question. In this way, the release of the roe may be ensured prior to the commencement of the operation, or the Commander may be sufficiently prepared to make the decision to release the roe at short warning when the need arises. A roe Release Authorisation Matrix may be used to provide an overview of the release authority levels for all implemented roe for an operation.225
It is also possible to use dormant roe, that is, roe that will become available when a predefined situation arises.226 For instance, the operation may initially take place below the threshold of armed conflict, but there is a real risk of the situation escalating. Because it takes time to develop new roe, the roe necessary for an armed conflict may be developed in advance and preapproved as part of a branch plan, ready for use if an armed conflict starts. In such circumstances it is important to clearly define who will have the authority to determine that the situation activating the roe has occurred. When the dormant roe are activated, the higher levels of command must be informed, including the nac.227 If the change is significant, such as when the plan to deter the adversary from creating an armed conflict has failed, the decision to transition into the branch plan and activate the dormant roe is likely to be taken at the level of the nac.
If a situation changes or a new need arises, making the existing roe insufficient, the roe may be updated.228 As those developing the roe would have been of the opinion that the existing roe are the most appropriate for the missions, a request for new roe are more likely to succeed if it can be demonstrated that there is a situation that the planners had not foreseen and that the existing roe do not fit.229 In nato, changing roe requires a roe request to be sent up through the chain of command. However, such requests must be authorised by nac, which means that the process may be very time consuming, depending on the operational and political complexity of the operation and the roe requested. It is therefore more likely that clarification on the application of a roe to a new situation is provided in, for instance, a tactical directive, or that the roe is retained due to the increase sensitivity of its application.
If instead the decision is made to no longer allow the use of an existing roe, perhaps because a type of operations is no longer going to be conducted, the roe may be cancelled. An example of such roe may be restrictions on conducting military exercises in the vicinity of a neighbouring, hostile state. If an armed conflict breaks out with that State, such a roe will likely no longer be relevant. While a local Commander may restrict the use of certain roe for forces under his or her command, the cancellation of a roe for all the forces must be done at the strategic level (i.e. the nac).
Last not but not least, in addition to the serial messages that make up the roe, nato roe will also contain a political policy statement (pps), reflecting the overall policy aim and providing the context for the mission. This statement will only be a short text, set out in the general text (gentext) at the introduction to the roe, reiterating the directions provided in the strategic documents for the operation.230 For instance, it may state that the overall purpose of the operation is to establish a safe and secure environment for the civilian population and/or to remove the threat posed by insurgency groups. The pps will be complemented by a political policy indicator (ppi), clarifying nac’s assessment of the effect nato’s efforts are intended to have on the situation.231 Phrased differently, the ppi describes the desired end-state. The ppi may be ‘de-escalation’, ‘maintain status quo’ or ‘risk of escalation is acceptable’.232 The pps and ppi should be taken into account when interpreting the roe. For instance, if the ppi is ‘de-escalate’, this should affect how and when attack roe are used, or how much force is used for example when securing the freedom of movement of nato forces. The ppi is therefore an important aspect of the roe, even if the short line containing it may be easy to overlook.
[k]nowing the exact circumstances under which an opposing force will resort to the use of deadly force would aid an adversary in planning a devastating preemptive [sic] attack. Additionally, the roe likely discloses the level of intelligence regarding an adversary’s forces, capabilities, tactics, and expected threats or actions and may reveal classified technology for determining enemy identities or threats.233
For instance, Parks explains that during the Vietnam War, the U.S. forces were not permitted to attack surface to air missiles (sams) that were located in populated areas. The North Vietnamese became aware of this, and began to place their sams and antiaircraft sites “adjacent to or within populated areas whenever possible”.234 Similarly, certain isaf forces were only permitted to attack opposing forces that were visibly armed. When this become known to the adversary, they would drop their weapons immediately after attacking isaf forces, knowing that they would not be attacked back.235
As a result, roe are usually classified. However, over the last decade there has been increasing public pressure on making the roe more available to others.236 Releasing parts of the roe may also be done to send a message to the opponent. For instance, during the abovementioned ‘Tanker war’, the U.S. made the decision to publicly announce that the roe had been expanded to permit the naval commanders to protect ships from friendly countries as well as U.S. ships. This has previously not been permitted, with the result that Iran began to attack such ships ‘right under the nose’ of the U.S. Navy. By making these changes known to the press, it was intended to “telegraph firm intentions to the Iranians”.237 Such openness about the use of military force may be important for democratic accountability and for public support of military operations. However, declassification of roe gives rise to obvious operational challenges both concerning force protection and mission accomplishment. Again, we see the need to find the appropriate way to strike a balance between political and operational considerations. Perhaps a better way to achieve these political gains is to inform more generally about ongoing operations, without including the level of details that roe represent. This way the desire for increased accountability may be taken into account, without enabling the opposing forces to predict how the forces will react to threats and possibly even what they are likely to do next.
2.5 roe as a Tool for Command and Control
The actions of military forces will arguably “either bring order or escalation”,238 and the roe are an important tool for controlling the direction of the forces and their impact on the situation.239 As Boddens Hosang explains, “[b]y controlling the use of force, roe can influence the actions taken by other parties (including opposing forces)”.240 In this final section of the roe chapter, the function of roe as a tool for command and control will be examined more closely.241
the functions of commanders, staffs, and other Command and Control bodies in maintaining the combat readiness of their forces, preparing operations, and directing troops in the performance of their tasks. The concept embraces the continuous acquisition, fusion, review, representation, analysis and assessment of information on the situation; issuing the commander’s plan; tasking of forces; operational planning; organizing and maintaining cooperation by all forces and all forms of support.242
This definition does unfortunately not make the meaning of C2 entirely clear, neither with regard to the respective roles of command and control, nor the relationship between them. As stressed in one nato doctrine, “[t]he terms command and control are not synonymous, although they share a close relationship and they are commonly used together”.243 In order to understand how roe function as a C2 tool, it is therefore useful to understand the distinction between command and control.
nato has defined command as both “[t]he authority vested in an individual of the armed forces for the direction, coordination, and control of military forces” and “the will of the commander expressed for the purpose of bringing about a particular action”.244 The will of the Commander may also be referred to as the Commander’s intent. AJP-01 further explain command to be “how a commander impresses their will and intentions on subordinates to achieve particular objectives”.245 Control is defined by nato as “[t]he authority exercised by a commander over part of the activities of subordinate organizations, or other organizations not normally under his or her command, that encompasses the responsibility for implementing orders or directives”.246 According to AJP-01, “[c]ontrol allows the commander to verify what actions have taken place and their effectiveness relative to the intent and the objectives set for the force to achieve”.247 Similar explanations are found in command and control theory. Pigeau and McCann describe the function of command as “to invent novel solutions to mission problems, to provide conditions for starting, changing and terminating control, and to be the source of diligent purposefulness”.248 According to Alberts and Hayes, control is intended to determine “whether current and/or planned efforts are on track. If adjustments are required, the function of control is to make these adjustments if they are within the guidelines established by command”.249 The essence of control should therefore be viewed as ensuring that the operation is carried out in compliance with the parameters set by command, especially Commander’s intent.250
Stated simply, command determines and defines the direction, while control ensures and enables the desired shift.251 Command includes control, and control enables command.252 In addition to control, command also includes the ability to define the intention for the operation and to identify and assign missions or tasks to forces. Because command includes authoritative direction over all aspects of military operations, including logistics, discipline and training, Troop Contributing Nations (tcn) to nato operations retain full command over their forces. Furthermore, tcns tend to only transfer operational control (opcon), not operational command (opcom).253
Although roe is commonly referred to as a command and control tool,254 it is perhaps first and foremost a tool for control. Control is the organisation, direction and coordination of forces and functions in order to execute Commander’s intent.255 By defining the parameters for the use of force and other provocative actions, roe enables control over how forces may deal with individual situations. roe also enable operational control over the use of force or other provocative acts by retaining the ability to authorise the use of certain roe at a given level of command. The ability to use roe as a control mechanism in this way is a result of the tendency in nato to require all use of force to be authorised by roe, unless it is self-defence; if the roe is retained, the forces cannot carry out that act.256 A Commander may decide to retain all use of a specific roe, such as attack on opposing forces not posing a threat at the time, or just the application of a roe to certain circumstances. For instance, roe for operations known to be at risk of causing collateral damage may require higher level authorisation, even if the expected losses are within what is permitted by the law of armed conflict under the proportionality rule.257 Another example may be to retain the authority to attack politically sensitive targets.
As with other forms of control, roe release authority may be delegated to lower levels of Command. To some extent this exercise of control may be viewed as a reflection of command; by delegating certain authorities while retaining others, Commander sends a signal of how the operation should be conducted.258 The Commander’s intent will, however, be better set out in supplementary documents such as sops and Tactical Directives.
Distinguishing between roe as either a command or control tool may give a false impression of the clarity of the distinction between those concepts, however. As mentioned above, the concepts are closely interlinked and interdependent, and command and control theory presents many different ways of understanding them.259 The following text will therefore deal with the concepts jointly, while bearing in mind the depth and multiplicity of C2.
roe have several potentials for being used as a C2 tool. First, as roe provide information on when, where, against whom and how force and other provocative acts may be used,260 they may be used to impose limitations on the type of situations where force may be used, within the parameter of what the law would permit, and they may set restrictions on where force may be used both to avoid unwanted escalation and to protect own forces. Furthermore, the roe may limit the use of force to persons posing some form of threat at the time or of certain importance, rather than permitting the use of force against all persons otherwise considered to be lawful targets. Finally, the roe may impose requirements on the degree of force to be used, for instance, whether it may include deadly force or not; whether escalation procedures must be applied; and what means and methods of warfare may be employed. As a result, the roe help reduce the risk of military forces acting in ways the Commander had not foreseen. From the perspective of subordinate Commanders, the roe provide them with clear boundaries within which they may exercise discretion and initiative.261
roe are often referred to as the Commander’s tool for command and control, including in this book. Blank, for instance, explains that “roe serve as a commander when the commander is not there”.262 It must, however, be borne in mind that the framework for using roe as a command and control tool is determined by the body that decides on the roe for a given operation, which for nato is the nac. Through the roe, nac imposes political control of the use of military force. For the Commander of the operation, the application of roe as a C2 tool is subject to the outer limits defined by the nac. Furthermore, as a result of the political consensus required to authorise nato roe, the roe are commonly not very detailed. This does comply with the view that roe should not be ‘rudder orders’;263 however, it also means that when the Commander wishes to provide further guidance on the use of force in order to make his or her intent clear, this must be done through other operational documents. As previously mentioned, sops, Tactical Directives and fragos are among the examples of alternative mechanisms. The more complex and politically sensitive the operation is, the greater the need for such guidance will be.264 Although this is an operational reality for nato, the fact that the direction on the use of force is scattered out among several documents has been a cause for frustration and confusion, and is in this regard unfortunate.265
The multinational realities of nato may also impact the effectiveness of roe as a Commander’s tool for command and control. First, as explained in Section 2.4.2, States are free to declare caveats both on their interpretation of how roe should be implemented and to limit the operational use of their forces. Second, States may at any time declare that they will not carry out ordered tasks on the basis of national considerations; what is referred to as “showing the national red card”.266 During the 1999 Kosovo campaign, for instance, General Sir Michael Jackson refused to use British forces to seize Pristina airfield because it was expected to result in “senseless escalation of hostilities with Russian forces”.267
The effectiveness of roe as a command and control tool will also depend on the authority the Commander in question has been delegated. For instance, a Commander who has been delegated tactical control over forces will be able to do less with those forces than the superior who has operational command over those forces.268 Furthermore, the use of roe as a command and control tool will be affected by the approach taken with command and control in general. For instance, the use of roe as a C2 tool will be different when applying a bottom-up approach to command and control as opposed to a top-down approach. The former approach, which is commonly referred to as mission command or decentralised command (Auftragstaktik in German or oppdragsbasert ledelse in Norwegian), is based on the principle that the Commander will decide what is to be achieved, but leave it to subordinate Commanders to decide how it should be done. The latter approach, on the other hand, is a form of centralised command, where detailed orders, for instance in the form of roe, enable top level control of the execution of tasks. While mission command requires a certain room of manoeuvre in order for the Commanders to exercise their discretion and initiative, centralised or detailed command discourages initiative and is commonly criticised for amounting to micromanagement.269 Detailed command reduces the scope for the Commander’s past experience, knowledge of threats to the forces, and understanding of the mission and the potential adversary to affect a decision to use force.270 Extensive and detailed control should in other words be applied with caution, albeit recognising that certain operations are so sensitive that centralised command is necessary.271 It is in other words important to find “the correct balance between encouraging creative command and controlling command creativity”.272
The nato command philosophy “promotes a decentralized style of command based on freedom and speed of action, and initiative, while remaining responsive to superior direction.”273 At the same time, it is emphasised that “the philosophy is flexible enough to allow commanders to exercise detailed command and command by veto according to the prevailing situation and type of joint force”.274 As a result, although the Commander’s ability to exercise command and control for instance through roe is limited by the parameters set by the nac, the focus on mission command in nato entails that those parameters will generally not be narrowly defined, thereby leaving Commanders the necessary flexibility to execute their mission.
As discussed in Section 2.4.1, roe are commonly criticised for not appropriately balancing operational and political considerations and thus for being either overly restrictive or overly permissive, depending on the perspective of the commentator. Command and control theory may therefore to some extent help explain this friction. What some consider to be overly restrictive and hence poorly drafted roe may in fact be a reflection of the decision to employ more detailed or centralised command.275 From the perspective of mission command, extensive use of detailed control will slow down the operation and undermine the relationship of trust within the organisation. This may destroy the will to take responsibility and to act on own initiative. The decentralised C2 approach will therefore favour roe that give the military forces more room to act on their own initiative and judgement. This should not, however, be misunderstood to mean that roe are less important under the decentralised command approach. According to Blank, “roe are at the center of this system of decentralized command and individual initiative – the parameters and guidance that roe provide to senior and junior commanders enable them to internalize the intent of the senior leadership and implement it on the ground”.276
[e]ven if roe are relatively well drafted and are fully understood by all relevant actors, they can nevertheless fail to produce the desired military action in the fog of crisis. The best roe cannot eliminate the dangers of escalation or vulnerability; they can only reduce the likelihood of incidents and increase the likelihood that when incidents occur, they will be of the sort (underreaction or overreaction) “preferred” by political leaders.278
Second, and related to the above, although roe play an important role as a C2 tool at the operational level, at the tactical level, the on-scene Commander is likely to rely more on training, briefing and direct leadership to direct the actions of the troops. Although this will be based on the applicable roe and other operation specific documents, the roe are likely to be translated into more concrete use of force guidance set out for instance in so-called soldier’s cards. However, even at this level, the roe will be important for communicating to other supporting or supported units or higher levels of command which authority is being relied upon or requested. For instance, if a unit is in need of support of another unit to get out of a difficult situation, especially if they are requesting close air support, they must be able to identify the roe authorising the action they are requesting.
As previously explained,279 different tcns may also have a different view on whether roe are legally binding or not. There is no international agreement on the legal status of roe, and the question is thus left to be determined by national legislations or policies. If roe are orders, non-compliance may result in punishment, while if roe are just guidance with little independent legal effect, not complying with them may not induce any consequences. With regard to those forces whose national legislation does not consider roe to be legally binding, this lack of ability to enforce compliance with roe arguably makes them a less effective tool for C2, compared to forces from countries that do.
Before leaving the topic of roe as command and control tool, it should be stressed that the quality of the roe cannot be determined from mission success alone, and vice versa; mission failure cannot necessarily be blamed on the roe. This is because mission success depends on many factors. Alberts and Hayes therefore argue that the quality of the command and control in an operation “should be directly measured by examining how well the functions of C2 have been performed”,280 rather than whether the expected results of the mission were achieved. It would for instance not be sufficient alone to have the ideal roe; the Commander must also have the appropriate means available and implement the roe well. As a result, while the aim is for roe to contribute towards mission success in the best possible way, when assessing the quality of roe, it is necessary to keep the influence of other factors in mind as well.281
2.6 Conclusions
There is a general call for increased control of the use of military force. This is possibly due to increased awareness of what happens in the battlefield, coupled with expectations that modern technology should not only minimise but completely remove the risk of mistakes being made. roe seem to be considered as one of the most suitable tools for such enhanced control, and as a result, there is an increased focus on roe and their use as a command and control tool, both in military circles and among politicians. The use of roe as a command and control tool may be less effective in a multinational than national context, but it nonetheless remains an important mechanism for the strategic level to impose political restraints on the use of force and other provocative acts. It enables Commanders to control the use of force and hence mission development and prioritisation.
The practice of using roe as a tool for command and control is not new, both in terms of historical examples and arguably also in its modern form, however, it appears that the use of nato roe has changed. A restrictive approach to nato roe, whereby all use of force or other acts which may be construed as provocative must be expressly authorised by roe, is increasingly applied to all types of nato operations. This appears to be a consequence of the desire for further control of the use of force. As a result, all use of force during such operations require roe authorisation, the only exception being the use of force in self-defence. In the next chapter, the ‘use of force’ categories in nato roe doctrine will be examined in further detail.
An earlier version of this chapter was published as an article: Camilla Guldahl Cooper, ‘Rules of Engagement Demystified: A Study of the History, Development and Use of ROEs’, 2014, Military Law and the Law of War Review / Revue de Droit Militaire et de Droit de la Guerre 53 (2), pp. 189–246.
Scott D. Sagan, ‘Rules of engagement’, in Alexander L. George (ed.), Avoiding war – Problems of Crisis Management (Westview Press, Oxford, 1991) p. 461.
U.S. Army, Legal Lessons Learned from Afghanistan and Iraq, Volume 1 (U.S. Army Judge Advocate General’s Legal Center and School, Center for Law and Military Operations, Charlottesville, Virginia, 2004)
nato, Military Decision on MC 362/1 – NATO Rules of Engagement [hereinafter MC 362/1], 30 June 2003, p. 2. The MC 362/1 is nato unclassified, however, permission to use parts of the document for the purposes of this research is granted by the nato Military Commission in document imstam(O&P)-0006-2018 (copy on file with the author). See also nato, STANAG 2597: Training in Rules of Engagement, ATrainP-4 [hereinafter: STANAG 2597], 4 May 2015, available at
nato, AAP-06(2017): Glossary of terms and definitions (nato Standardization Office, Edition 2017). The definition was included in the glossary on 01 Jan 1973, and was changed in 2018 to reflect the MC 362/1 definition. See nato, AAP-06(2018): Glossary of terms and definitions (nato Standardization Office, Edition 2018).
Alan Cole et al., Sanremo Handbook on Rules of Engagement (International Institute of Humanitarian Law, 2009) p. 1.
UN Department of Peacekeeping Operations/Military Division, Guidelines for the development of rules of engagement (ROE) for United Nations peacekeeping operations, UN Doc. MD/FGS/0220.0001 [May 2002] p. 1.
UN Department of Peacekeeping Operations, Handbook on Multidimensional Peacekeeping Operations (United Nations, December 2003) p. 57.
Council of the European Union, Use of Force Concept for EU-led Military Crisis Management Operations (1st revision, Doc. 6877/06 of 28 February 2006), cited in Peter Dreist, ‘Rules of Engagement in multinationalen Operationen – ausgewählte Grundsatzfragen’, 49(3) Neue Zeitschrift für Wehrrecht 99 (2007), p. 107.
U.S. Army, Operational Law Handbook (U.S. Army Judge Advocate General’s Legal Center and School, International and Operational Law Department, Charlottesville, Virginia, 2017) p. 77.
Canadian Forces, Use of Force for CF Operations, Joint Publication 5.1 (Document B-GJ-005-501/FP-001, issued under the authority of the Chief of the Defence Staff, 2008) p. 2–3.
Great Britain, British Defence Doctrine, Joint Defence Publication (jdp) 0–01 (4th edition, November 2011, Chief of Defence Staff,
Norwegian Armed Forces, Manual i krigens folkerett (Trans: Manual of the Law of Armed Conflict), issued under the authority of the Chief of the Defence, [2013], [hereinafter referred to as Norwegian LOAC Manual], p. 295, author’s translation.
Mark David Maxwell, ‘Individual Self-Defense and the Rules of Engagement: Are the Two Mutually Exclusive?’, 41 Mil. L. & L. War Rev. 39 (2002), p. 41.
Daniel P. O’Connell, The Influence of Law on Sea Power (Manchester University Press, Manchester, 1975) p. 169.
Sagan, ‘Rules of engagement’ (n 2) p. 444.
Canadian Forces, Use of Force for CF Operations (n 11) p. 2–4.
See also Gary P. Corn, ‘Developing Rules of Engagement: Operationalizing law, policy and military imperatives at the strategic level’, in Geoffrey S. Corn, Rachel E. VanLandingham and Shane R. Reeves (eds.), U.S. Military Operations – Law, Policy and Practice (Oxford University Press, Oxford, 2016) p. 212.
On the threshold of armed conflicts, see Section 1.3.1.
See e.g. undpko/md, Guidelines for the development of rules of engagement (ROE) for United Nations peacekeeping operations (n 7), attachment 1, p. 2, rules 2 and 3 dealing respectively with the use of weapon systems such as riot control equipment and the authority to carry weapons.
See also Corn, ‘Developing Rules of Engagement’ (n 18) p. 212.
See e.g. U.S. Army, Operational Law Handbook (n 10) p. 77.
nato, Allied Joint Publication 3.9: Allied joint doctrine for joint targeting (AJP-3.9), (nato Standardization Office (nso), Edition A Version 1, 31 July 2017),
jcs Pub 1, Department of Defense Dictionary of Military and Associated Terms (Washington, DC, U.S. Govt. Print. Off., 1979) p. 298, cited in Ashley Roach, ‘Rules of engagement’, 36(1) US Naval War College Review 46 (Jan/Feb 1983), p. 46. See also U.S. Army, Operational Law Handbook (n 10) p. 83, and nato, STANAG 2597, (n 4) p. B-65.
Roach, ‘Rules of engagement’ (n 24) p. 46.
Sagan, ‘Rules of engagement’ (n 2) p. 451.
See e.g., Guy R. Phillips, ‘Rules of Engagement: A Primer’, The Army Lawyer, Department of Army Pamphlet 27-50-248 (July 1993), p. 5; and Maxwell, ‘Individual Self-Defense and the Rules of Engagement’ (n 14) p. 42, though Maxwell accredits the quote to General Israel Putnam rather than William Prescott. See also U.S. Army, Legal Lessons Learned from Afghanistan and Iraq, Vol. 1 (n 3) p. 81.
See also discussion in Corn, ‘Developing Rules of Engagement’ (n 18) pp. 213–214.
Gary D. Solis, The Law of Armed Conflict: International humanitarian law in war (Cambridge University Press, Cambridge, 2016) p. 474.
See also Hans Boddens Hosang, Rules of Engagement (PhD thesis, University of Amsterdam 2017, available at
According to nato, “spins are intended to provide information, and direction and guidance that apply to a longer period than just the intended ato period or to more than one part of the ato. spins should not contain already established procedures.” nato, Allied Joint Doctrine 3.3 for Air and Space Operations (AJP-3.3) (nato Standardization Office (nso), Edition B Version 1, April 2016, available at
nato, AAP-06(2018) (n 5), “A set of instructions covering those features of operations which lend themselves to a definite or standardized procedure without loss of effectiveness. The procedure is applicable unless ordered otherwise.” Also known as standard operating procedure.
nato, AAP-06(2018) (n 5), a directive is “A military communication in which policy is established or a specific action is ordered.”
The restricted target list (rtl) “is a joint target list subset owned by the jfc and may include some joint prioritized target list targets. They are lawful targets that have temporary or permanent operational restrictions for engagement and require special consideration.” nato, Allied Joint Publication 3.9: Allied joint doctrine for joint targeting (AJP-3.9), (nato Standardization Office (nso), Edition A Version 1, 31 July 2017),
The no-strike list (nsl) “is comprised of entities that are designated by the nac as protected. Engagement of nsl entities violates international law, the Law of Armed Conflict, agreements, conventions, nac policies or rules of engagement.” ibid, pp. 4–8 and 4–9.
nato, AAP-06(2018) (n 5), “An abbreviated form of an operation order, issued as required, that eliminates the need for restating information contained in a basic operation order. It may be issued in Sections.”
nato, AAP-06(2018) (n 5), fire control is “The control of all operations in connection with the application of fire on a target.”
U.S. Army, Legal Lessons Learned from Afghanistan and Iraq, Vol. 1 (n 3) p. 83. See also, Randall Bagwell and Molly Kovite, ‘It is not self-defence: Direct participation in hostilities authority at the tactical level’, 224(1) Military Law Review 1 (2016), p. 11.
“roe appear in a variety of forms in national military doctrines, including execute orders, deployment orders, operational plans, or standing directives. Whatever their form, they provide authorisation for and/or limits on, among other things, the use of force, the positioning and posturing of forces, and the employment of certain specific capabilities.” Cole et al., Sanremo Handbook on Rules of Engagement (n 6) p. 1.
See e.g. Frits Kalshoven and Thyla Fontein, ‘Some Reflections on Self-Defence as an Element in Rules of Engagement’ in Mariëlle Matthee etc. (eds.), Armed Conflict and International Law: In Search of the Human Face (tmc Asser Press, The Hague, 2013) pp. 103–104, and Christopher D. Amore, ‘Rules of Engagement: Balancing the (Inherent) Right and Obligation of Self-Defense with the Prevention of Civilian Casualties’, 1 National Security Law Journal 39 (spring 2013), pp. 59ff.
The civcas Directives are further commented on in Sections 2.4.1 and 5.5.
U.S. Army, Legal Lessons Learned from Afghanistan and Iraq, Volume 2 (U.S. Army Judge Advocate General’s Legal Center and School, Center for Law and Military Operations, Charlottesville, Virginia, 2004,
U.S. Army, Legal Lessons Learned from Afghanistan and Iraq, Vol. 1 (n 3) p. 83.
Bradd C. Hayes, Naval Rules of Engagement: Management Tools for Crisis (rand/ucla Center for the Study of Soviet International Behavior, Santa Monica (CA), No. rand/-N-2963-CC, 1989, available at
Boddens Hosang, however, argues that “roe cannot even be said to be a primus inter pares in the panoply of operational guidance and operational directives given for an operation”. Hans Boddens Hosang, ‘Rules of Engagement and Targeting’, Chapter 8 in Paul AL Ducheine, Michael N. Schmitt, and Frans Osinga (eds.), Targeting: The Challenges of Modern Warfare (Asser Press, 2016) p. 173.
See also Jeffrey F. Addicott, ‘The Strange Case of Lieutenant Waddell: How Overly Restrictive Rules of Engagement Adversely Impact the American War Fighter and Undermine Military Victory’, 45 St. Mary’s Law Journal 1 (2013), pp. 20–21.
Wesley Morgan, ‘Weighing threats and rules of engagement’, New York Times (23 August 2010,
See also Ian David Park, The Right to Life in Armed Conflict (Oxford University Press, Oxford, 2018) p. 121, explaining that “within the UK military justice system, disregarding a tactical directive may amount to a contravention of an order and therefore amount to a military disciplinary offence”.
Boddens Hosang, ‘Rules of Engagement and Targeting’ (n 44) p. 173.
See e.g. U.S. Chairman of the Joint Chiefs of Staff (cjcs), Standing Rules of Engagement (SROE)/Standing rules for the use of force (SRUF) for U.S. Forces [hereinafter: SROE/SRUF], cjcs Instruction 3121.01B (13 June 2005) p. A-2. See Michael N. Schmitt, ‘Clipped Wings: Effective and Legal No-fly Zone Rules of Engagement’, 72 International Law Studies Chapter xii (1998), p. 250.
Gary P. Corn, ‘Should the Best Offense Ever be a Good Defense? The Public Authority to Use Force in Military Operations: Recalibrating the Use of Force rules in the Standing Rules of Engagement’, 49 Vanderbilt Journal of Transnational Law 1 (2016), pp. 54–55.
Michael N. Schmitt, ‘Targeting and International Humanitarian Law in Afghanistan’, 85 International Law Studies 307 (2009), pp. 337–338, fn. 91.
nato roe does not include roe on the use of force in self-defence. This is left for the respective tcns to regulate.
Lone Kjelgaard, ‘The Importance of Law in the Theatre’, in Edoardo Greppi, Conduct of hostilities: the Practice, the Law and the Future, Proceedings of the 37th Round Table on Current Issues 2014 (International Institute of Humanitarian Law, 2015,
Despite this position, the MC 362/1 still makes reference to self-defence, and applies self-defence terminology in some of its roe. See nato, MC 362/1 (n 4) p. 4, and nato, STANAG 2597 (n 4) pp. B17–18. This issue will be dealt with further in Chapter 8, while the law pertaining to self-defence is examined in Chapter 6.
The sroe is intended to “establish fundamental policies and procedures governing the actions to be taken by U.S. commanders and their forces during all military operations and contingencies and routine Military Department functions occurring outside U.S. territory (…) and outside U.S. territorial seas”. U.S. cjcs, SROE/SRUF (n 49) p. A-1. In U.S. J.P. 5-00.2, it is further explained that the sroe is intended to be “stand alone guidance for US forces worldwide that are equally applicable to all the combatant commands and can be easily and quickly amended or clarified to meet mission-specific requirements”. U.S. Joint Chiefs of Staff, Joint Publication 5-00.2: Joint Task Force Planning Guidance and Procedures (13 January 1999,
See also J.F.R. Boddens Hosang, ‘Self-Defence in Military Operations: The Interaction between the Legal Bases for Military Self-Defence and Rules of Engagement’, 47 Military Law and Law of War Review 25 (2008), p.77.
nato, AAP-06(2018) (n 5), defines an oplan as: “[a] plan for a single or series of connected operations to be carried out simultaneously or in succession. It is usually based upon stated assumptions and is the form of directive employed by higher authority to permit subordinate commanders to prepare supporting plans and orders. The designation “plan” is usually used instead of “order” in preparing for operations well in advance. An operation plan may be put into effect at a prescribed time, or on signal, and then becomes the operation order.”
On nato roe development, see further Section 2.4.
Dormant roe are further explained in Section 2.4.2.
For more information, see
nato, Allied Command Operations Comprehensive Operations Planning Directive COPD V2.0 (Supreme Headquarters Allied Powers Europe (shape), Belgium, 04 October 2013).
Suggestions have been made to include standing roe in the update of the MC 362/1, however, this work was not completed by the time of the publication of this book.
The U.S. standing roe, for instance, “focus primarily on providing implementation guidance on the exercise of self-defence.” Corn, ‘Developing Rules of Engagement’ (n 18) p. 226.
See e.g. nato, MC 362/1 (n 4) pp. 5–6; Sylvain Fournier, ‘nato Intervention Abroad: How Roe Are Adopted and Jurisdictional Rights Negotiated’, Stefano Manacorda and Adán Nieto Martin (eds.): Criminal Law between War and Peace: Justice and Cooperation in Criminal Matters in International Military Interventions: Proceedings of the XVth International Congress on Social Defense (Ministerio de Justicia, Spain, 2009) p. 117, and Roach, ‘Rules of engagement’ (n 24) p. 49.
See also U.S. Army, Operational Law Handbook (n 10) p. 479.
Permissive roe in this sense are also referred to as ‘the Nelson touch’. The impact of restrictive or permissive roe in this sense of the terms is further discussed in Section 2.4.1.
U.S. Army, Operational Law Handbook (n 10) p. 477. See further p. 80, where the same terms are used to describe roe measures requiring express permission or where anything not restricted may be deemed permitted.
nato, STANAG 2597 (n 4) p. B-8. See also U.S. Army, Operational Law Handbook (n 10) p. 477, and Nikoleta-Paraskevi Chalanouli and Sherrod Lewis Bumgardner, ‘Rules of Engagement, nato’s Approach and National Caveats’, in Barbara Janusz-Pawletta (ed.), Zasady użycia siły (ang. Rules of Engagement) – wybrane problemy prawne [Rules of Engagement – legal problems] (Towarzystwo Wiedzy Obronnej, Warsaw, 2011) p. 107.
See nato, MC 362/1 (n 4) p. 2.
See further Section 2.2.2.1.
See Section 2.2.1.4.
According to stanag 2597, “The MC 362/1 distinguishes between nato roe for peacetime operations from armed conflict operations by authorizing the use of force in peacetime and limiting the use of force during armed conflict. However, for policy reasons, the distinction is no longer as certain, and current nato roe are a mixture of authorisations and limitations for all types of operations”. nato, STANAG 2597 (n 4) p. B-28.
See also U.S. Army, Operational Law Handbook (n 10) p. 479.
For a criticism of the changed methodology in regard to isaf, see Wolff Heintschel von Heinegg and Peter Dreist, ‘The 2009 Kunduz Air Attack: The Decision of the Federal Prosecutor-General on the Dismissal of Criminal Proceedings Against Members of the German Armed Forces’, 53 German Yearbook of International Law 833 (2010), p. 856.
North Atlantic Treaty, Washington, D.C, 4 April 1949 (
Heintschel von Heinegg and Dreist, ‘The 2009 Kunduz Air Attack’ (n 74) pp. 842 and 864. See also discussion pp. 850–853. See further Erica L. Gaston, ‘Reconceptualizing Individual or Unit Self-Defense as a Combatant Privilege’, 8(2) Harvard National Security Journal 283 (2017), p. 305.
Common Article 2 common to GC I-IV, found e.g. in Geneva Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field (GC I) [1949], Laws of Armed Conflict, printed in Dietrich Schindler and Jiri Toman, The Laws of Armed Conflicts (Martinus Nijhoff Publisher, 1988) pp. 459ff. On the classification of armed conflict, see further Section 1.3.1.
See Section 2.4.2 for further detail on nato roe drafting.
The application of treaty law in national legislation depends on whether the State in question has taken a dualistic or monistic approach to international law. However, this is beyond the scope of this book.
Vienna Convention on the Law of Treaties (vclt) [23 May 1969], U.N. Doc. A/CONF.39/27 [1969], reprinted in 8 I.L.M. 679 (1969), Article 5.
ibid, Article 2(1)(a). The requirement of treaties being agreements ‘governed by international law’ is also found in Article 1 of the Vienna Convention on the Law of Treaties between States and International Organizations or between International Organizations [21 March 1986] UN Doc.A/CONF.129/15 [1986], reprinted in 25 I.L.M. 543 (1986).
un ilc, ‘Draft Articles on the Law of Treaties With Commentaries’, Yearbook of the International Law Commission [1966], Vol. ii, UN. Doc. A/CN.4/SER.A/1966/Add.l (
Aegean Sea Continental Shelf (Greece v Turkey), Judgement, I.C.J. Reports [1978] 3, pp. 39–44.
Anthony Aust, Modern treaty law and practice (Cambridge University Press, Cambridge, 2013) p. 17.
Jan Klabbers, The Concept of Treaty in International Law (Kluwer Law International, The Hague, 1996) p. 109. See also pp. 108–116.
Benedict Kingsbury, Nico Krisch, and Richard B. Stewart, ‘The Emergence of Global Administrative Law’, 68(3/4) Law and contemporary problems 15 (2005), p. 17.
Aust, Modern treaty law and practice (n 84) p. 49.
See e.g. Gunther Moritz, ‘The Common Application of the Laws of War within the nato-forces’, 13 Mil. L. Rev. 1 (1961), p. 2.
nato, AAP-42 nato Glossary of standardization terms and definitions (nato, Brussels, September 2011) ‘nato Regulation’.
North Atlantic Treaty (n 75).
Moritz, ‘The Common Application of the Laws of War within the nato-forces’ (n 88) p. 3.
See also Chalanouli and Bumgardner, ‘Rules of Engagement, nato’s Approach and National Caveats’ (n 68) pp. 113–114.
vclt (n 80) Articles 31 sets out general rules of interpretation for treaties. On the application of public international law on interpretation to agreements made by international organisations, see for instance Martti Koskenniemi, ‘The Fate of Public International Law: Between Technique and Politics’, 70(1) Modern Law Review 1 (2007), pp. 16–17.
On historic and current rules of treaty interpretation, see e.g. Richard Gardiner, Treaty Interpretation (Oxford University Press, Oxford, 2008) Chapter 5.
Caveats are further explained in Section 2.4.2 below.
See also Corn, ‘Developing Rules of Engagement’ (n 18) p. 222.
See nato, MC 362/1 (n 4) p. 2.
On customary law development, see Section 6.3.1.4. See also Antonio Cassese, International Law (2. ed., Oxford University Press, Oxford, 2005) pp. 153–169.
Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of victims of International Armed Conflicts (Protocol I) [1977], printed in Schindler and Toman, The Laws of Armed Conflicts (n 77) pp. 711ff, Article 51(3), and Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of Non-International Armed Conflicts (Protocol II) [1977], ibid, pp. 775ff., Article 13(3).
Direct participation in hostilities and its application to organised armed groups is examined further in Section 5.2.3.
See also Jody M. Prescott, ‘Tactical Implementation of Rules of Engagement in a Multinational Force Reality’, in Geoffrey S. Corn, Rachel E. VanLandingham and Shane R. Reeves (eds.), U.S. Military Operations – Law, Policy and Practice (Oxford University Press, Oxford, 2016) p. 253. It should be pointed out that nato roe concerning hostile act only cover those hostile acts that do not constitute actual attack, as it would otherwise impose restrictions on the right of self-defence, such as when the roe were to be retained. The same applies to the hostile intent roe; nato roe only cover those displays of hostile intent that do not constitute imminent attack, as imminent attacks would give rise to a right of self-defence. The nato hostile act and hostile intent roe are further explained in Section 3.5, and their relationship to loac as their legal basis is examined in Chapter 11. As a result, the reservations mentioned in the icrc Interpretive Guidance on dph concerning the use of practice on hostile act and hostile intent in relation to dph is not applicable. icrc, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law [hereinafter ICRC Interpretive Guidance] (May 2009, prepared by Nils Melzer, available at
Fournier, ‘NATO Intervention Abroad’ (n 64), pp. 117–118, footnotes omitted. See also Sherrod Lewis Bumgardner et al., NATO Legal Deskbook (act Staff Element Europe, Belgium, 2010, available at
Stanislav Horvat (ed.), The Rule of Law in Peace Operations (Proceedings of the 17th International Congress, Scheveningen, xvii Recueil of the International Society for Military Law and the Law of War, Brussels, 2006).
ibid, p. 136. See also commentary on the questions in Boddens Hosang, Rules of Engagement (n 30) pp. 337–341.
Horvat (ed.), The Rule of Law in Peace Operations, ibid, National responses: ‘Albania’, p. 163; ‘Austria’, p. 190; ‘Czech Republic’, p. 388; ‘Denmark’, p.235; ‘Germany’, p. 171; ‘Italy’, p. 264; ‘Luxemburg’, p. 313; ‘Norway’, p. 324; ‘the Netherlands’, p. 334; ‘Sweden’, p. 376; and ‘u.s.a’., p. 266. The answers from Bulgaria, Poland and Spain seem to imply that roe are orders, but are not sufficiently clear to permit a definite conclusion: ‘Bulgaria’: “there is no need to have specific orders to apply [roe]” (p. 221); ‘Poland’: “roe are legally binding on paf as long as they are placed in a commander’s oporder (…). Commander’s orders must always be obeyed by all soldiers / subordinates unless the orders are breaches of international or national criminal law.” (p. 345); ‘Spain’: “roe, after being adopted by the authority in charge of the operation and disseminated to participant Units though the proper chain of command, are mandatory and therefore legally binding for the forces (…). Therefore, any conduct in violation of roe adopted by Spain would constitute at least an infraction of disciplinary order.” (p. 258).
See also judgement by the Dutch Military Chamber of the Court of Appeal of Arnhem in the Eric O. case, where it was held that the Rules of Engagement constituted official instructions. Eric O. case, Gerechtshof Arnhem [Arnhem Court of Appeal] 21-006275-04 (4 May 2005, ljn: AT4899,
Horvat (ed.), The Rule of Law in Peace Operations (n 103) p. 232. Belgium explains that: “roe are not considered to be an order as such but rather part of an order or guidelines imposed by an order. Once imposed by an order, roe will be applied as such, unless they require an additional order for some instances of use of force”. (‘Belgium’, p. 211); Greece replied that “The roes are not considered as orders (…)” (‘Greece’, p. 277); while the Latvian answer is that “roe can not [sic] be considered to be orders” (‘Latvia’, p. 301).
ibid, ‘Greece’, p. 277, and ‘Latvia’, p. 301.
ibid, ‘Belgium’, p. 211, and ‘Croatia’, p. 232.
A similar approach may be found in Poland and Spain, two of the countries that were unclear on whether roe are orders in themselves. ibid, ‘Poland’, p. 258, and ‘Spain’, p. 345. Luxemburg, on the other hand, despite having answered that roe are military orders, provides a less clear answer on whether they are legally binding: “They are binding in the absence of other provisions which regulate the use of force in crisis.” (Author’s translation from French, ibid. ‘Luxemburg’, p. 312).
In light of the other responses, the most controversial approach is that of Sweden. Although not a nato member, Sweden is a PfP-country which participates in nato-led operations such as isaf. Despite stating that roe are orders, the answer goes on to state that: “roe (…) are not legally binding” (ibid, ‘Sweden’, p. 376). Unlike other States which do not consider roe in themselves to be legally binding military orders, the Swedish answer provides no information on how roe could potentially become legally binding.
See also Corn, ‘Developing Rules of Engagement’ (n 18) p. 213.
For a more comprehensive overview, see Mark S. Martins, ‘Rules of Engagement for Land Forces, A Matter of Training, Not Lawyering’, 143 Military Law Review 1 (Winter 1994), pp. 33–55; Hayes, Naval Rules of Engagement (n 43) pp. 37–56, and Corn, ‘Developing Rules of Engagement’ (n 18) pp. 213–217.
Roach, ‘Rules of engagement’ (n 24) p. 49.
Commando order [498-PS, Pros. Ex. 124] issued on 18 October 1942, reprinted in: United States vs. Wilhelm von Leeb et al. (‘The High Command Trial’), Judgment of 27 October 1948, U.S. Military Tribunal Nuremberg, Law Reports of Trials of War Criminals (Published for the United Nations War Crimes Commission by His Majesty’s Stationary Office, London, 1949) Vol. xi, p. 526.
Hays Parks, ‘Deadly Force is Authorized’, 127(1) US Naval Institute Proceedings 35 (January 2001), p. 33. For examples of the opposite approach, see Amore, ‘Rules of Engagement’ (n 40) pp. 51–53, and Michael S. Reilly, The Rules of Engagement in the Conduct of Special Operations (Naval Postgraduate School Thesis, 1996, available at
Brian T. O’Donnell and James C. Kraska, ‘International Law of Armed Conflict and Computer Network Attack: Developing the Rules of Engagement’, 76 International Law Studies 395 (2002), pp. 399–400.
Corn, ‘Developing Rules of Engagement’ (n 18) p. 214. O’Connell claims that the expression is a Malta coinage of the 1960s, but does not provide any sources for this: O’Connell, The Influence of Law on Sea Power (n 15) p. 169.
O’Donnell and Kraska, ‘International Law of Armed Conflict and Computer Network Attack’ (n 116) p. 400.
Scott R. Morris, ‘Rules of Engagement: Origin, Practical Use, Doctrinal Integration, and Theoretical Concept’ (1994) (unpublished article on file with the clamo), referred to in Martins, ‘Rules of Engagement for Land Forces’ (n 112) p. 35. See also Solis, The Law of Armed Conflict (n 29) p. 476.
Corn, ‘Developing Rules of Engagement’ (n 18) pp. 214–215.
nato, Report by the International Planning Team to the Standing Group on Rules for Engagement of Unidentified Aircraft by nato Fighters in Peacetime, Ref. IPT 152/39 (2nd Revised Final Draft), 28 August 1956 (
Martins, ‘Rules of Engagement for Land Forces’ (n 112) p. 36.
ibid, p. 47.
macv – Military Assistance Command, Vietnam.
L.E. Paterson, Project CHECO Southeast Asia Report: Evolution of the Rules of Engagement for Southeast Asia, 1960–1965, Pacific Air Forces HICKAM AFB HI CHECO DIV, 1966 (
William R. Peers, Report of the Department of the Army Review of the Preliminary Investigations into the My Lai Incident, United States Department of the Army, 1974, Books i and ii, Volume iii: ‘Exhibits’.
Martins, ‘Rules of Engagement for Land Forces’ (n 112) p. 37.
121(14) U.S. Congressional Record 17558 [1975] (United States Government Printing Office, Washington, 1975).
Project checo report 1969, reprinted in 131(13) U.S. Congressional Record 5248 [1985] (United States Government Printing Office, Washington, 1985).
ibid.
ibid.
ibid.
Hays Parks, ‘Rolling Thunder and the Law of War’, 33(2) Air University Review 2 (Jan/Feb 1982), p. 12.
ibid, p. 21.
Daniel Gouré and Rebecca Grant, U.S. Naval Options for Influencing Iran (Lexington Institute, April 2009,
See Hayes, Naval Rules of Engagement (n 43) pp. 37ff for a useful case study of U.S. roe during the Iran-Iraq war.
John G. Humphries, ‘Operations Law and the Rules of Engagement in Operations Desert Shield and Desert Storm’, 11(3) Airpower Journal Fall 25 (1992), p. 28.
ibid, p. 29. See also William R. Hittinger, ‘Rules of Engagement As A Force Multiplier’, CSC 2000 (
Humphries, ‘Operations Law and ROE in Operations Desert Shield and Desert Storm’ (n 137) p. 28.
Hays Parks, ‘Rules of Engagement: No More Vietnams’, US Naval Institute Proceedings, March 1991, 27, p. 27.
Humphries, John G., ‘Operations Law and ROE in Operations Desert Shield and Desert Storm’ (n 137) p. 29.
See e.g. Parks, ‘Deadly Force is Authorized’ (n 115).
Schmitt, ‘Clipped wings’ (n 49) p. 246, footnote omitted. The nca consists of the President and the Secretary of Defense.
Boddens Hosang, ‘Rules of Engagement and Targeting’ (n 44) p. 164.
ibid.
See Bumgardner et al., NATO Legal Deskbook (n 102), pp. 254–255. See also jdp 0–01 British Defence Doctrine (n 12) p. 1–24; U.S. Army, Operational Law Handbook (n 10) pp. 77–78, and Norwegian LOAC Manual (n 13) p. 296. The Canadian ‘Use of Force for CF Operations’ also lists a fourth aspect of roe; diplomatic considerations, referred to as: “the collective objectives of the alliance or coalition” (Canadian Forces, Use of Force for CF Operations (n 11) p. 2–5), as does Ashley Roach in his much-cited 1983 article ‘Rules of Engagement’ (n 24) p. 48.
U.S. Army, Operational Law Handbook (n 10) pp. 77–78.
Margaret Thatcher, The Downing Street Years: 1979–1990 (1993), p 201, quoted in, Jody M. Prescott, ‘Tactical Implementation of roe’ (n 101) p. 249.
See e.g. U.S. Army, Operational Law Handbook (n 10) p. 78; Roach, ‘Rules of engagement’ (n 24) p. 48 and Fournier, ‘nato Intervention Abroad’ (n 64) p. 116.
jdp 0–01 British Defence Doctrine (n 12) p. 1–24.
Kjelgaard, ‘The Importance of Law in the Theatre’ (n 53) p. 38.
ibid. The concept of ‘caveats’ is dealt with in further detail in Section 2.4.2 below.
The concept of command or superior responsibility has developed as customary law for centuries, but is in its modern form considered to be developed in the (controversial) 1945 Yamashita case, 327 U.S. 1 (1946). The core of the concept is that commanders may be held criminally liable to the acts of their subordinates, either because the Commander ordered the acts or because he/she knew or should have known about it, but did not use the means at his/her disposal to prevent the crimes from occurring. For a formulation of a current standard of command responsibility, see e.g. AP I (n 99) Articles 86–87.
The Venn-diagram initially introduced by Roach consisted of four circles, the last being diplomacy, but this has usually not included in current presentations. See Roach, ‘Rules of engagement’ (n 24) p. 48.
Sagan, ‘Rules of engagement’ (n 2) p. 451.
Applicable law is to a large extent constant, especially for iacs and niacs respectively. However, it should be noted that the result of the application of loac is in many areas context dependent. This is because loac rely to a large extent on subjective norms such as proportional, necessary, and feasible, which allow for the subjective assessment by those responsible, based on the information available at the time and their reasonable analysis and understanding of this information.
On the difference between iacs and niacs, see Section 1.3.1.
See also Boddens Hosang,, ‘Rules of Engagement and Targeting’ (n 44) pp. 163–163.
Sagan, ‘Rules of engagement’ (n 2) p. 444.
The terms restrictive and permissive are here used to describe the degree of political control over the use of force. This must be distinguished from the debate on whether roe consist of either authorisations or restrictions, depending on whether it is a peace operation or armed conflict, or whether roe provide the sole authority for the use of force during all operation, as discussed in Sections 2.2.1.5-2.2.1.8 above.
Hayes, Naval Rules of Engagement (n 43) p. 21.
See also Todd C. Huntley, ‘Balancing Self-Defense and Mission Accomplishment in International Intervention: Challenges in Drafting and Implementing Rules of Engagement’, 29 Maryland Journal of International Law 83 (2014), p. 86.
Sagan, ‘Rules of engagement’ (n 2) p. 451. See also Huntley, ‘Balancing Self-Defense and Mission Accomplishment’, ibid, p. 86.
General Charles Krulak introduced the phrase “strategic corporal” in ‘The Strategic Corporal: Leadership in the Three Block War’, Marines Magazine, January 1999. Krulak explained that “In many cases, the individual Marine will be the most conspicuous symbol of American foreign policy and will potentially influence not only the immediate tactical situation, but the operational and strategic levels as well. His actions, therefore, will directly impact the outcome of the larger operation; and he will become, as the title of this article suggests – the Strategic Corporal.” (p. 5).
Criticising the tendency of micromanagement, Hays Parks draws upon the following examples: “Senior leaders who authorize air strikes, naval bombardments, and cruise missile attacks with slight attention to roes are for some reason drawn to the fine details of ground force roes like moths to a flame. A senior officer in the Carter administration sought to require the forces executing the ill-fated April 1980 Iranian rescue mission to shoot to wound. During the Reagan administration, Marines in Beirut were subjected to roe tampering at all levels, contributing to the deaths on 23 October 1983 of 241 service personnel in the Marine barracks bombing. Personal weapons (pistols only) for U.S. military advisers in El Salvador were specified in a National Security Council meeting. In the opening moments of Operation Just Cause, four Seals from seal Team Four dies and nine were seriously wounded in their seizure of Paitilla airfield, and the mission and members of seal Team Two in Balboa Harbor were jeopardized, in large measure because of unnecessarily restrictive roes. roes a carrier battle group commander and his seniors would reject out of hand were imposed from higher level down through the chain of command without so much as a hiccup from the SEALs’ intermediate commanders.” Parks, ‘Deadly Force is Authorized’ (n 115) p. 34, emphasis added.
Parks, ‘Rules of Engagement: No More Vietnams’ (n 140) p. 27. For more examples of the challenge to manage civilian control and military command, see Hayes, Naval Rules of Engagement (n 43) pp. 22–25.
O’Connell, The Influence of Law on Sea Power (n 15) p. 173.
The so-called “isaf civcas Directives” are examples of this tendency (see below and Section 5.5). See also Erica L. Gaston, When Looks Could Kill: Emerging State Practice on Self-Defense and Hostile Intent (Global Public Policy Institute, 2017,
Addicott, ‘The Strange Case of Lieutenant Waddell’ (n 45) p. 4.
The isaf Tactical Directive regarding civilian casualties (civcas) was first issued in June 2007 by the then-isaf Commander (comisaf) General Dan McNeill in response to a May 2007 isaf report discussing the effect of civilian casualties caused by an April 2007 U.S. air strike in Shindand, Herat province. See Center for Civilians in Conflict, Civilian Harm Tracking: Analysis of ISAF Efforts in Afghanistan (2014,
See also: Bob Dreyfus, ‘Mass-Casualty Attacks in the Afghan War’, The Nation (19 September 2013, t
See e.g. nato LibGuide, Counterinsugence Strategy, (
See e.g. Paul Szoldra, ‘Marine: Strict Rules of Engagement Are Killing More Americans Than Enemy in This Lost War’, Business Insider (24 Aug. 2012,
Letter from Peter Olson, Legal adviser to nato, to the International Commission of Inquiry on Libya, 23 January 2012, cited in Corn, ‘Developing Rules of Engagement’ (n 18) p. 240. See also nato, STANAG 2597 (n 4) p. B-51, and Kjelgaard, ‘The Importance of Law in the Theatre’ (n 53) p. 40.
Parks, ‘Rules of Engagement: No More Vietnams’ (n 140) p. 27.
Spiegel Staff, ‘Obama’s Lists – A Dubious History of Targeted Killings in Afghanistan’, Spiegel Online (28 December 2014,
Schmitt, ‘Targeting and IHL in Afghanistan’ (n 51) pp. 320–321, citing Headquarters United States Air Force, Operation Anaconda: An Airpower Perspective 42–43 (2005), available at
Park, The Right to Life in Armed Conflict (n 47) p. 120.
Clausewitz, Carl von, On War (Michael Howard and Peter Paret (eds/trs), Princeton University Press, Princeton NJ, 1984) p. 607.
Hayes, Naval Rules of Engagement (n 43) p. 2.
Richard K. Betts, ‘Is Strategy an Illusion?’, 25 International Security Fall 2 (2000), p. 37, paraphrasing a conversation about Clausewitz in Richard Henrick’s Crimson Tide (Avon, New York, 1995, p. 75).
Peter D. Feaver, ‘The Civil-Military Problematique: Huntington, Janowitz, and the Question of Civilian Control’, 23 Armed Forces & Society 149 (1996), p. 170.
Hayes, Naval Rules of Engagement (n 43) p. 25.
See Reilly, ROE in the Conduct of Special Operations (n 115) pp. 32ff, especially p. 39, for a detailed study of how roe become translated down through the chain of command. See also Laurie Blank, ‘Rules of Engagement: Law, Strategy and Leadership’, in Carol Connelley and Paolo Tripodi (eds.), Aspects of Leadership – Ethics, Law and Spirituality (Marine Corps University Press, Quantico, Virginia, 2012) p. 241, concerning the restrictive implementation of isaf tactical directives on the prevention of civilian casualties.
Although not a roe, a good example of such additional limitations is the isaf Tactical Directives on Civilian Casualties. In order to ensure compliance with the directives, subordinate commands introduced the additional limitation that weapons could never be fired inside a village. This was not what com isaf intended, and as a result, the 2010 version of the Tactical Directive emphasised that additional restrictions could not be imposed (“Subordinate commanders are not authorized to further restrict this guidance without my approval”). Extracts of the 1 August 2010 version of the Tactical Directive were published in isaf News Release 2010-08-CA-004. According to Pennekamp, another common, and by some argued overused, tool used by commanders to regulate the soldiers’ use of force, is Escalation of Force Procedures (Aaron Pennekamp, ‘Standards of Engagement: Rethinking Rules of Engagement to More Effectively Fight Counterinsurgency Campaigns’, 101 The Georgetown Law Journal 1619 (2013), pp. 1634–1635). Escalation of force procedures are considered further in Sections 3.5.3.3 (as a tool for identifying hostile act and hostile intent) and 8.2.5.2 (as a tool to ensure proportionate use of force in self-defence).
U.S. Army, U.S. Operational Law Handbook (n 10) p. 83.
ibid.
Hays Parks, ‘Righting the Rules of Engagement’, 115(5) US Naval Institute Proceedings 83 (May 1989), p. 86.
ibid.
Sagan, ‘Rules of engagement’ (n 2) p. 450.
See e.g. the criticisms voiced by Sagan, ibid.
Reilly, roe in the Conduct of Special Operations (n 115) p. 32.
nato Standardised Agreement.
nato, STANAG 2597 (n 4). The present author was a member of this working group, and one of the prime authors of the training package.
saceur is “[t]he nato strategic commander commanding Allied Command Operations and responsible for the planning and execution of nato operations.” nato, AAP-06(2018) (n 5). saceur is one of nato’s two strategic commanders and is the head of Allied Command Operations (aco). nato Topics, Supreme Allied Commander Europe (SACEUR),
Chalanouli and Bumgardner, ‘Rules of Engagement, NATO’s Approach and National Caveats’ (n 68) p. 102.
Fournier, ‘nato Intervention Abroad’ (n 64) p. 116, and Peter Dreist, ‘Rules of Engagement in nato Operations – Application in Germany’s Legal System’, in Barbara Janusz-Pawletta (ed.), Zasady użycia siły (ang. Rules of Engagement) – wybrane problem prawne [Rules of Engagement – legal problems] (Towarzystwo Wiedzy Obronnej, Warsaw, 2011) p. 119.
Attack in nato roe only refers to situations when forces may attack individuals or objects, for instance, because they pose a threat or are members of the opposing forces. It does not include questions of individual self-defence, which is left to national regulation, or state self-defence, as regulated by the jus ad bellum.
nato, STANAG 2597 (n 4) p. B-7.
Kjelgaard, ‘The Importance of Law in the Theatre’ (n 53) p. 38.
ibid.
This is signified by the indicator desig. nato, STANAG 2597 (n 4) p. B-62. See also Boddens Hosang, ‘Rules of Engagement and Targeting’ (n 44) p. 166.
nato, STANAG 2597 (n 4) p. B-75.
ibid, pp. B-45–46. For an overview of the operational planning process, see Boddens Hosang, Rules of Engagement (n 30) pp. 82–86.
James C. Duncan, ‘The Commander’s Role in Developing Rules of Engagement’, 52(3) Naval War College Review 76 (Summer 1999), p. 85.
The Military Committee (MC) is the senior military authority in nato. According to nato “It is the primary source of military advice to the North Atlantic Council and the Nuclear Planning Group, and gives direction to the two Strategic Commanders. (…) As such, it is an essential link between the political decision-making process and the military structure of nato.” nato Topics,
The North Atlantic Council (nac) is: “the principal political decision-making body within nato. It oversees the political and military process relating to security issues affecting the whole Alliance. It brings together representatives of each member country to discuss policy or operational questions requiring collective decisions, providing a forum for wide-ranging consultation between members on all issues affecting their peace and security. (…) Policies decided in the nac are the expression of the collective will of all member countries of the Alliance since decisions are made on the basis of unanimity and common accord.” nato Topics,
See nato, STANAG 2597 (n 4) pp. B-64–70.
U.S. Army, Operational Law Handbook (n 10) p. 474.
Fournier, ‘nato Intervention Abroad’ (n 64) p. 116. See also Kjelgaard, ‘The Importance of Law in the Theatre’ (n 53) p. 38, where she explains that “In the case of Libya, for example, Germany was able to join consensus on the mandate for Operation Unified Protector despite having abstained on Security Council Resolution 1973 of 11 March 2011, the basis for the nato operation, and being unprepared to participate in the operation itself”.
Such cards are not a substitute for training in roe, but serve as useful memory tools. For examples, see U.S. Army, Operational Law Handbook (n 10) pp. 101–106.
nato defines a caveat as: “any limitation, restriction or constraint by a nation on its military forces or civilian elements under nato command and control or otherwise available to nato, that does not permit nato commanders to deploy and employ these assets fully in line with the approved operation plan.
Note: A caveat may apply inter alia to freedom of movement within the joint operations area and/or to compliance with the approved rules of engagement.” nato, AAP-06(2018) (n 5).
U.S. Army, Operational Law Handbook (n 10) p. 478.
nato, STANAG 2597 (n 4) p. B-76.
Fournier, ‘nato Intervention Abroad’ (n 64) p. 117.
See e.g. an overview of operational impacts of caveats in Chalanouli and Bumgardner, ‘Rules of Engagement, nato’s Approach and National Caveats’ (n 68) pp. 109–110. See also nato, Resolution 336 on Reducing National Caveats, nato Parliamentary Assembly, prepared by International Staff, 15 November 2005, document no. 238 sesa 05 E, available at
Prescott, ‘Tactical Implementation of roe’ (n 101) p. 263.
O’Connell, The Influence of Law on Sea Power (n 15) p. 170.
nato, STANAG 2597 (n 4) p. B-46.
Bumgardner et al., NATO Legal Deskbook (n 102) p. 258, and Duncan, ‘The Commander’s Role in Developing Rules of Engagement’ (n 204) p. 85.
Parks, ‘Deadly force is authorized’ (n 115) p. 35.
See Section 2.2.1.8.
nato, STANAG 2597 (n 4) p. B-8.
Reilly, ROE in the Conduct of Special Operations (n 115) p. 26, fn. 33.
nato, STANAG 2597 (n 4) p. B-74.
Boddens Hosang, Rules of engagement (n 30) p. 56.
nato, STANAG 2597 (n 4) p. B-71. See also Bumgardner et al., NATO Legal Deskbook (n 102) p. 256. The concept was introduced in the redrafting of the MC 362. Boddens Hosang, Rules of Engagement (n 30) p. 54.
Boddens Hosang, Rules of engagement, ibid, pp. 54–55.
For an explanation of roe review in general, see Prescott, ‘Tactical Implementation of ROE’ (n 101) pp. 268–274.
U.S. Army, U.S. Operational Law Handbook (n 10) p. 82.
nato, STANAG 2597 (n 4) p. B-50.
ibid. See also Prescott, ‘Tactical Implementation of ROE’ (n 101) p. 273.
nato, STANAG 2597 (n 4) p. B-50.
Phillips, ‘Rules of Engagement: A Primer’ (n 27) pp. 4–5.
Parks, ‘Rolling Thunder and the Law of War’ (n 133) p. 10.
A similar problem has been reported from the war in Iraq: “The marines say insurgents know the rules, and now rarely carry weapons in the open. Instead, they pose as civilians and keep their weapons concealed in cars or buildings until just before they need them. Later, when they are done shooting, they put them swiftly out of sight and mingle with civilians.” Chivers, C. J., ‘Perfect Killing Method, but Clear Targets Are Few for Marines in Iraq’, New York Times (22 November 2006,
See e.g. Peter Rowe, ‘The Rules of Engagement in Occupied Territory: Should They be Published?’, 8 Melbourne J. Int’l L. 327 (2007). According to the nato Legal Deskbook, “roe were for many years kept classified, but over the past decade this is less and less often the case, as awareness of roe and their importance has spread to politicians, journalists, and laymen. It is now believed that bringing roe into the open discourse is of benefit”. Bumgardner et al., NATO Legal Deskbook (n 102) p. 254.
Hayes, Naval Rules of Engagement (n 43) pp. 53–54.
ibid, p. 57.
ibid.
Boddens Hosang, ‘Rules of Engagement and Targeting’ (n 44) p. 164.
Command and control theory is a separate field and a thorough study of C2 theory is beyond the scope of this book. For a general introduction to command and control in nato operations, see e.g.: nato, Allied Joint Publication 01: Allied Joint Doctrine (AJP-01) (nato Standardization Office (nso), Edition E, Version 1, February 2017)
nato, AAP-06: Glossary of terms and definitions (E) 1988, cited in David S. Alberts and Richard E. Hayes, Understanding Command and Control (ccpr Publications, 2006,
nato, AJP-01(E) (n 241) p. 5–2.
nato, AAP-06(2018) (n 5).
nato, AJP-01(E) (n 241) p. 5–3.
nato, AAP-06(2018) (n 5).
nato, AJP-01(E) (n 241) p. 5–3.
Ross Pigeau and Carol McCann, ‘Re-conceptualising Command and Control’, Canadian Military Journal, Spring 2002, 53, p. 56.
Alberts and Hayes, Understanding Command and Control (n 242) p. 59.
ibid. See also Pigeau and McCann, ‘Re-conceptualising Command and Control’ (n 248) p. 56.
Alberts and Hayes, Understanding Command and Control (n 242) p. 19–20.
Or as explained in AJP-3(B): “Control is inherent in command”. nato, Allied Joint Publication 3: Allied Joint Doctrine for the Conduct of Operations (AJP-3) (nato Standardization Agency (nsa), Edition B, March 2011) p. 1–12.
Prescott, ‘Tactical Implementation of ROE’ (n 101) p. 263. See also nato, AJP-01(E) (n 241) p. 5–5, and Chalanouli and Bumgardner, ‘Rules of Engagement, NATO’s Approach and National Caveats’ (n 68) p. 113.
nato, AAP-06(2018) (n 5) provides the following definitions of opcom and opcon: “Operational command (opcom): The authority granted to a commander to assign missions or tasks to subordinate commanders, to deploy units, to reassign forces, and to retain or delegate operational and/or tactical control as the commander deems necessary. Note: It does not include responsibility for administration.” “Operational Control (opcon): The authority delegated to a commander to direct forces assigned so that the commander may accomplish specific missions or tasks which are usually limited by function, time, or location; to deploy units concerned, and to retain or assign tactical control of those units. It does not include authority to assign separate employment of components of the units concerned. Neither does it, of itself, include administrative or logistic control.”
See e.g. Corn, ‘Developing Rules of Engagement’ (n 18) p. 212.
nato, AJP-3(B) (n 252) p. 1–12.
See further Section 2.2.1.7.
As Schmitt explains, this was a prominent practice in Afghanistan, and “reflected an understanding that unintended civilian harm can have extra-normative consequences”. Schmitt, ‘Targeting and ihl in Afghanistan’ (n 51) p. 321.
See also Blank, ‘Rules of Engagement’ (n 183) p. 249, where she explains that “roe do more than give guidance for specific uses of force and other actions during military operations. They provide the link to communicate the commander’s intent”.
See e.g. Pigeau and McCann, ‘Re-conceptualising Command and Control’ (n 248) p. 53, and Alberts and Hayes, Understanding Command and Control (n 242) p. 7.
See e.g. Sagan, ‘Rules of engagement’ (n 2) pp. 445ff.
See also Addicott, ‘The Strange Case of Lieutenant Waddell’ (n 45) p. 20: “On the positive side, roe can serve a useful purpose by providing the solider with specific guidance on when, where, and how to use force.”
Blank, ‘Rules of Engagement’ (n 183) p. 256. The concept is further explained on pp. 249–255. See also Schmitt, ‘Clipped Wings’ (n 49) p. 246.
See Section 2.2.1.2.
See e.g. Reilly, ROE in the Conduct of Special Operations (n 115) pp. 27–28, and Parks, ‘Righting the Rules of Engagement’ (n 187) p. 187.
According to Addicott, “The use of so-called “tactical directives” has made a noteworthy contribution to the confusion surrounding roe.” Addicott, ‘The Strange Case of Lieutenant Waddell’ (n 45) p. 20. See further Section 2.2.1.3.
Prescott, ‘Tactical Implementation of ROE’ (n 101) p. 263. See also nato, STANAG 2597 (n 4) p. B-77.
Prescott, ‘Tactical Implementation of ROE’, ibid, p. 262.
For definitions of opcom and opcon, see note 253. nato, AAP-06(2018) (n 5) defines tacom and tacon as: Tactical command (tacom): “The authority delegated to a commander to assign tasks to forces under his command for the accomplishment of the mission assigned by higher authority.” Tactical control (tacon): “The detailed and, usually, local direction and control of movements or manoeuvres necessary to accomplish missions or tasks assigned.”
See e.g. Pigeau and McCann, ‘Re-conceptualising Command and Control’ (n 248) p. 57; U.S. Joint Chiefs of Staff, Mission Command White Paper, Washington, DC, 3 April 2012,
According to Sagan, these are among the factors that should influence the decision to use force. Sagan, ‘Rules of engagement’ (n 2) p. 451.
From the Norwegian ffod, 2014, p. 166, describing the Norwegian approach to mission command (“ffod: “Sterk ordrestyring må brukes med forsiktighet: Utstrakt bruk av detaljstyring er tempodrepende, undergraver tillitsrelasjonene i organisasjonen og ødelegger viljen til å ta ansvar og å handle selvstendig på eget initiativ”). Forsvarsstaben (Norwegian Defence Command), Forsvarets Fellesoperative Doktrine (Norwegian Joint Operational Doctrine), 2014,
Pigeau and McCann, ‘Re-conceptualising Command and Control’ (n 248) p.57.
nato, AJP-01(E) (n 241) p. 5–1.
ibid.
See also Blank, ‘Rules of Engagement’ (n 183) pp. 223 and 239–244. Other reasons why the isaf roe were considered too restrictive are misapprehension of the legal and operational requirements of such coin operations. ibid, pp. 244–247.
ibid, p. 238.
Sagan, ‘Rules of engagement’ (n 2) p. 462.
ibid.
See Section 2.2.2.2.
Alberts and Hayes, Understanding Command and Control (n 242) p. 33.
ibid, p. 67.