From Passive Consent to Self-Defence after the Syrian Protest against the US-led Coalition

Since September 2014, the US and some Arab States have conducted air strikes against Islamic State (IS) in Syria. They have recently been joined by some Western States, including the UK, Canada, Australia and France. The justification given by those States and the US for their military operations in Syria is based on the right of self-defense, enshrined in Article 51 of the UN Charter. Such justification has been contested by some scholars. Yet, this does not mean those air strikes should be considered unlawful. It is argued that they could be justified by the “passive consent” of Syria.

1. The end of passive consent

Contrary to their reaction to air strikes conducted by States such as Turkey, Syrian authorities did not formally oppose air strikes by the US-led coalition after they occurred – although some limited objections have been formulated in the media. The Assad regime even seems to have welcomed this international effort to fight against IS and expressed its readiness to cooperate with such effort. As a result, although consent has never been expressly given by the Assad regime to the US-led coalition’s airstrikes, the absence of protest by this regime could be interpreted as “passive consent” thereto. Such interpretation could find some support in the DRC v. Uganda case (para. 46), in which the ICJ inferred the DRC’s consent to the presence of Uganda troops on its soil from the absence of any objection to such presence.

Yet, regardless whether “passive consent” is a valid legal basis for justifying the airstrikes conducted by the US-led coalition against IS in Syria, such legal basis seems now to be in great trouble. Indeed, the Assad regime recently sent two letters, one dated 16 September and the other one dated 17 September 2015, in which it contests the intervening states’ interpretation of Article 51 of the UN Charter. In the second letter, it officially warns that “[i]f any State invokes the excuse of counter-terrorism in order to be present on Syrian territory without the consent of the Syrian Government whether on the country’s land or in its airspace or territorial waters, its action shall be considered a violation of Syrian sovereignty”.

Two arguments could be invoked in order to maintain that “passive consent” nonetheless remains a possible legal justification. First, opposition to the airstrikes only comes from the Assad regime and not from the Syrian National Coalition (SNC), which is actually in favour of these airstrikes. However, the SNC is far from being universally recognized as the only legitimate government of Syria, whose consent would be enough to justify any invited use of force on the Syrian territory. Second, it could be argued that the Assad regime’s attitude is basically similar to the one adopted by the Pakistani authorities regarding the US drone strikes in Pakistan, which used to criticize those strikes publicly while secretly cooperating with the US and therefore tacitly agreeing to – at least some of – the US military operations. Yet, in the Syrian case, besides the fact that any cooperation between the US-led coalition and Assad regime must still be proven, protest has been formulated by the latter in such general and official terms, in the two aforementioned letters addressed to the UNSC, that it would be difficult not to consider them as expressing its true legal position.

2. Critical focus on self-defence

Should one therefore consider the airstrikes which are still conducted by the US-led coalition in Syria as amounting to an armed attack, and Syria as having the right to respond to it in self-defence? This in turn raises the question of the validity of the legal argument officially invoked by the US and the other Western States in order to justify their military intervention in Syria, i.e. the right of self-defence. Such question therefore appears as very critical. While the argument of individual self-defence, as recently and quite surprisingly invoked by the UK for justifying a specific military operation in Syria, can hardly be admitted, the same cannot be said with respect to the argument of collective self-defence, which all the intervening States (including the UK) have (also) invoked. It is a fact that Iraq is the object of ongoing armed attacks by IS from Syria and has requested other States to help it to defend itself against such attacks. It is increasingly admitted that private armed attacks, i.e. attacks committed by non-State actors in which no State is substantially involved, may amount to an armed attack in the sense of Article 51 of the UN Charter and trigger the right of self-defence of the victim State. In the Syrian case, no objection has been raised on this point.

However, the justification invoked by the intervening States is not without concern. This is not so much because of the controversial status of the unwilling or unable test that some of those States, including the US, Canada and Australia, have referred to in their justification, when they argued that self-defence was permissible because Assad was unwilling or unable to prevent IS from launching attacks against Iraq from Syrian territory. It is true that the existence of this test under international law remains contested in legal literature, notably because it is sometimes conceived as amounting itself to an “exception to international law’s cardinal prohibition on the use of force”, which would authorize the undertaking of any action in self-defence not normally allowed under the classical conception of the law of self-defence. Yet, it has not been rejected as such in the Syrian case, neither by Syria in its formal complaints submitted to the UNSC, nor by any other States. In addition and more fundamentally, one may arguably support, in line with some scholars, that such a test is merely part of the much broader and well-established condition of necessity of that law, which requires, in one of its main aspects, that self-defence be undertaken as a last resort, when there is no other reasonably available means for the victim State to protect itself against an armed attack. Indeed, relying on the (military) action of the State from whose territory private armed attacks originate, i.e. the territorial State, in order to stop those attacks appears as one of the best alternative means for the victim State to protect itself against such attacks. In that sense, the unavailability of this means, because of the unwillingness or inability of the territorial State to tackle the attacks, increases the necessity of the action in self-defence.

The main concern rather stems from the fact that the intervening States refuse to cooperate with the Assad regime to fight against IS in Syria although this regime proposed such cooperation. This problem is particularly difficult to disentangle in clear legal terms not only because of the lack of any detailed justification by the intervening States on such refusal but also because of the lack of any clear guidance under the law of self-defence on such issue. This issue may be first addressed in relation to the aforementioned unwilling or unable test. Disagreements may indeed arise on whether this test is satisfied in a particular case, precisely because of the absence of any more specific criteria for assessing its fulfillment. As a result, the intervening States may consider (as some do) that the Assad regime is in fact unwilling to tackle the attacks committed by IS, despite its offer to cooperate and its effort to show, notably in its second aforementioned letter sent to the UNSC, that any allegation of unwillingness is totally unfounded.

However, the issue should rather be addressed in relation to the aforementioned general condition of necessity in the more arguable case in which it is established or the intervening States consider that the Assad regime is in fact willing but still unable to stop attack by IS from being launched from Syrian territory. Although the unwilling or unable test would be satisfied in such a case, this would not be enough to justify any action in self-defence. According to the condition of necessity, that the test is only a part thereof, the victim State must have considered the (other) reasonable alternatives at its disposal in order to protect itself, especially any cooperation with the territorial State if the latter is only unable but not unwilling to prevent the private armed attacks being launched from its territory. The Assad regime’s offer to cooperate would therefore appear as a promising alternative to self-defence for protecting Iraq against IS.

Yet, the problematic question is whether such a means may be considered as “reasonably available”. Again, it is difficult to provide any precise answer to that question given the absence of any clear criteria provided under the law of self-defence in this respect. Although purely political reasons could hardly justify not seeking the consent of the territorial State, it is important to note that the military measures adopted in the framework of the Syrian consent would be dependent upon the conditions laid down by the Assad regime. As formally stated in the second aforementioned letter addressed to the UNSC, “[c]ombatting terrorism on Syrian territory requires close cooperation and coordination with the Syrian Government in accordance with the counter-terrorism resolutions of the Security Council”. One may wonder if such a “close” coordination does not make the Syrian consent a reasonably unavailable or ineffective means at the disposal of the intervening States for protecting Iraq. This could indeed limit the ability of the intervening States, possibly acting under the direction of the Assad regime, to take the necessary measures to protect Iraq against the attacks from IS. Moreover, in case of cooperation regarding intelligence information, this could be abused by the Assad regime, enabling it to pursue objectives such as weakening the rebel opposition groups which it also considers as terrorists.

That having been said, no such elaborated explanation has been given by any of the intervening States. In addition, things have got even more complicated these last days. Although it seems difficult to deny that, at least until recently, the Assad regime has proved unable to prevent IS from using Syrian territory in order to launch attacks on Iraq, its new cooperation with foreign States, mainly Russia, could lead to another conclusion on this ability test and, as a consequence, on the necessity of any action in self-defence in Syria. It is not an accident that the formal protests were formulated by the Assad regime just before it started its cooperation with Russia.