1 Introduction
A coastal State may take all necessary measures in accordance with international law to protect its territorial waters—its peace, good order or security—from the conduct of harmful activities by foreign vessels. Yet the matter becomes more complicated when such activities are carried out by foreign state vessels and do not amount to armed attack on the coastal State, which triggers its right of self-defense to use force to repel the attack. Since its law enforcement measures could, depending on circumstances, lead up to the prohibited use of force against the foreign flag State, the coastal State would need to take careful steps to avoid escalating the situation into the use of force and armed conflict, particularly where it forcibly evicts those vessels from its territory.
Against this background, this presentation aims to offer the optimal legal framework for de-escalating a coastal State’s maritime law enforcement action against foreign-flagged State vessels—namely warships and other government ships on non-commercial service—navigating in its territorial sea in order to protect its territorial waters as a peaceful maritime engagement without using prohibited armed force. In doing so, I examine three possible options for the legal basis for the coastal State’s action: (1) the coastal State’s right of protection against non-innocent passage under Article 25.1 of unclos (The UN Convention on the Law of the Sea); (2) a general right of self-protection against a forcible threat to a state’s legal rights; (3) the right of an injured state to resort to countermeasures under the law of state responsibility.
1.1 Option 1: The Coastal State’s Exercise of the unclos Right of Protection against Non-innocent Passage in Its Territorial Sea
The right of self-protection for a coastal State would be the first and foremost legal basis to be considered and relied upon as it is provided in Article 25(1) unclos that is a treaty provision. As such, some would think that it offers the
Article 25(1) does not say anything about the contour of its law enforcement action against harmful activities by foreign state vessels. Thus, some opine that the coastal State is entitled to do anything to protect its territorial waters against foreign state vessels to the extent that it does not amount to the prohibited use of force. On the flip side, others argue that Article 25(1) must be read in conjunction with other unclos provisions that limit maritime law enforcement action taken by the coastal State, highlighting Article 30 and Article 32. Article 30 only permits the coastal State to require foreign warships “to leave the territorial sea immediately,” meaning that the coastal State is not allowed to conduct any compulsory measures against foreign flag state vessels because Article 32 does provide “nothing in this Convention affects the immunities of warships and other government ships operated for non-commercial purposes.” But, as those diverging views show, the issue remains controversial among international law experts, combined with the scarcity of relevant state practice surrounding Article 25(1) on the coastal State’s right of protection.
In this way, the first option is beset by the unresolved issue of whether and to what extent the protective action is inhibited by the immunity and inviolability of foreign state vessels under the unclos regime, which would undermine the legality of the action in question and, as such, runs the risk of escalating the situation into the use of force between the coastal State and the foreign flag State.
1.2 Option 2: The Coastal State’s Exercise of the General Right of Self-Protection against Forcible Threats to Its Maritime Rights
Alternatively, the coastal State may rely on a general right of self-protection against a forcible threat to its legal rights in emergency situations other than armed attack. As such, this general right does not involve the inherent right of self-defense against armed attack as enshrined in Article 51 of the UN Charter. It has rather been invoked to warrant forcible intervention or minor uses of force that does not amount to the prohibited use of force in the sense of Article 2(4) of the UN Charter. Indeed, the existence of this right was hinted by the icj Judgement in the Corfu Channel case. In that case, the United Kingdom sent warships into Albanian territorial waters and carried out minesweeping operations therein, and the court found the British violation of Albanian sovereignty. What needs to be noted here is that the icj did not find the British violation of the prohibition on the use of force, but instead found its violations
All that said, it is also true that this general right of self-protection has not necessarily attained wide explicit recognition by many states. Besides, there is another thorny issue of how to reconcile this general right of protection with the Caroline doctrine or the Webster Formula on the inherent right of self-defense against imminent threat—which is not limited to armed attack—that the United States has long asserted to warrant its use of force. As such, even if the coastal State seeks to justify its law enforcement actions against foreign state vessels under the general right of protection and argues that those actions are distinct from the prohibited uses of force, the flag State of those foreign state vessels and other states like the United States might still consider them as the prohibited uses of force unless otherwise justified in self-defense or under the authorization by the UN Security Council. If that happens, the second option could end up providing the foreign flag State with the justification for its self-defense against the coastal State’s unlawful armed attack on its vessels, inviting the escalation of the use of force between the two. Relying on this second option would thus also likely endanger the situation between the coastal State and the foreign flag State, even granting that the act taken by the costal State vessel is minor or moderate use of force against foreign state vessels.
1.3 Option 3: The Coastal State’s Exercise of the Right to Take Countermeasures against Illegal Entry into Its Territorial Sea
In contrast, the third option, which concerns countermeasures by the coastal State against the violation of its territorial waters caused by the foreign state vessel’s non-innocent passage, is more tenable and instrumental in averting the interstate use of force and armed conflict, compared to other two options. The law of countermeasures is not just a well-established rule of international law on the circumstances precluding wrongfulness, which could justify the coastal State’s possible infringement of the immunity and inviolability of foreign state vessels. It also comprehends its own institutional mechanism for de-escalation that is composed of dynamic safeguard procedures to ensure the
As provided in arsiwa, the countermeasures taken by the coastal State as an injured state shall not involve the use of force in the sense of Article 2(4) of the UN Charter, but, at the moment, there are divergent views on the threshold of the use of force. Some argue that a hostile intent of the state in question is the crucial element for the qualification, and others contend that the intensity of armed violence is everything in the end. Yet whichever of these positions is adopted, de-escalating the situation between the coastal State and the foreign flag State would reduce the hostile intent and the amount of force employed in the situation. Lawful countermeasures, namely proportionate and temporary or reversible countermeasures, aimed at inducing the responsible state to cease the wrongful conduct, and resuming the performance of the obligation breached, would highly likely contribute to the peaceful settlement of the situation between the coastal State and the foreign flag State without the resort to the prohibited use of force. It is therefore not too much to say that among these three options, the option of countermeasures most fits the purpose of peaceful maritime engagement even in such a tense situation.
2 Conclusion
Either of these three options could be relied upon by the coastal State to justify its protective action against the foreign state vessels navigating within its territorial sea. Yet, the foregoing analysis brings us to conclude that the optimal legal framework for the coastal State’s protective action in this case is its right to take countermeasures.
It must be admitted that the first two options on the right of protection—namely the unclos right of protection for coastal States and the general right of self-protection for sovereign states—remain highly controversial when applied to a situation where the coastal State forcibly evicts foreign state vessels from its territory. Further, due to their unstable legal bases, these options
The same risk of escalation would also apply to the countermeasures option. However, not only does this option provide the solid legal foundation for the enforcement measures by the coastal State even if it inhibits the immunity and inviolability of foreign state vessels, but its own institutional mechanism for de-escalation also renders it more conducive to the peaceful settlement of conflicts and disputes between those states compared to the other two options that contain no such mechanisms. Apart from the issue of to what extent that mechanism could be workable in actual practice, no one can deny its potential to open a window of opportunity for the peaceful settlement of conflicts and disputes between the states concerned.