Withdrawing from Syria – The Illegality of Continued U.S. Presence post-ISIS

With Bashar al-Assad’s increasing control over the Western half of Syria, and the advance of U.S. backed forces in the East, the Syrian civil war has entered a new phase. Till date, these two campaigns have managed to largely remain separate, but as the ISIS threat shrinks, Syrian and U.S. backed forces are converging on the same cities. With every passing day, the purported legitimacy of a U.S.-led intervention in Syria decreases. This article shall analyse the possible justifications for the U.S. intervention in Syria, and assess their legality. Further, it shall assess the impact of the impending defeat of ISIS (in Syria) on these justifications where applicable.

Ever since the U.S.’s active military involvement in Syria began with the September 2014 strikes on ISIS forces in Syria, the U.S. has been careful to avoid providing any explicit legal justification for its actions. This leaves in question the legal basis of the U.S.’s military intervention in Syria.

In November 2015, the Security Council adopted Resolution 2249, which called upon member states to “take all necessary measures, in compliance with international law, in particular with the United Nations Charter,” against ISIS on Syrian and Iraqi soil. One justification that has been provided for the U.S.’s intervention is that it was authorised by the aforementioned resolution.

This justification is however contestable. This is because while Resolution 2249 uses language similar to the language used in Resolutions adopted under Chapter VII of the UN Charter authorising the use of force, the text of Resolution 2249 does not include any mention of Chapter VII. As there is no explicit mention of Chapter VII in Resolution 2249 it is highly debatable that the Resolution does indeed authorise the use of force. Where UN member States are not authorised to use force by the Security Council via a Resolution adopted under Chapter VII, they remain bound by the general prohibition on the use of force under Article 2(4) of the Charter. A reliance on Resolution 2249 for the U.S.’s intervention is thus contentious.

A further issue with relying on Resolution 2249 as an authorisation is that even if it were to be accepted as a legal justification, it would only apply while ISIS retained control over substantial portions of Syria. This is because Resolution 2249 explicitly calls on states “to eradicate safe havens they (ISIS) have established in Iraq and Syria”. Currently, Assad, backed by Russia and Iran, is on his way to a resounding victory over both ISIS and the U.S. backed rebel forces. It appears that the days of a strong ISIS presence in Syria are almost over. Once Assad regains control over the remaining ISIS held regions, the United States would lose any justification for further presence in Syria on this ground.

The question still remains whether in the absence of authorisation from the Security Council the U.S.-led coalition have a legal basis for military action in Syria.

In 2014, Iraq requested the U.S. to lead the fight against ISIS and it expressly consented to a U.S.-led intervention in Iraq. In a letter addressed to the United Nations, Iraq emphasised that: “with due regard for complete national sovereignty and the Constitution, we have requested the United States of America to lead international efforts to strike ISIS sites and military strongholds, with our express consent.” The U.S. airstrikes thus began against ISIS in Iraq based on the legal justification of ‘intervention upon invitation’. There was however neither an invitation nor express consent from the Syrian government for the U.S.-led air strikes.

A possible justification for the U.S.’s intervention stems from an interesting invocation of Article 51 of the U.N. Charter, the other exception to the Article 2(4) prohibition on the use of force. Proponents of this justification claim that the U.S.-led coalition is exercising collective self-defence against the ISIS.

The ground on which self-defence is being invoked is that Syria has been ‘unwilling or unable’ to control ISIS in its territories and this has necessitated the U.S. taking action to protect itself. This justification is however problematic, as the ‘unwilling or unable’ doctrine has not been widely accepted except by the U.S. and its allies.

Further, the ICJ has consistently held that Article 51 of the UN Charter limits self-defensive acts against non-state actors to situations in which the non-state actor’s armed attacks are in any way imputable to the state whose territorial sovereignty is being violated. This was the Court’s position in Nicaragua, which was thereafter reaffirmed in both the Palestinian Wall Advisory Opinion and DRC v. Congo. As ISIS is a non-state actor and its actions are not imputable to the Syrian state, the U.S. cannot invoke self-defence against ISIS.

Another purported justification for the intervention is the claim that the U.S. recognises the National Coalition of Syrian Revolutionary and Opposition Forces (the rebels) as the sole legitimate representative of the Syrian people, and that the Coalition has ‘given consent’ to the U.S. to help it in overthrowing the Assad regime. This justification is however problematic, as consent can only be given by the legitimate government of a State. The National Coalition lacks cohesiveness and more importantly, sufficient territorial control, and thus any recognition of it as the legitimate government of Syria is merely a political act.

A majority of the U.N. member states still recognize the Assad regime, and continue to share diplomatic relations with it. Thus, the legal recognition of the Assad regime as the legitimate government of Syria is still intact. Bearing this in mind, any act of forcible intervention in Syria to aid the opposition against the Assad regime would be in direct violation of the principle of non-intervention, as recognized by the ICJ in Nicaragua. Therein, the Court held that “the principle of non-intervention involves the right of every sovereign state to conduct its affairs without outside intervention”.

The final legal justification provided for the U.S. intervention is the prevention of the use of chemical weapons. The use of chemical weapons constitutes a violation of customary international law. It should be noted that although Syria is not a party to the 1993 Chemical Weapons Convention, it is bound by the 1925 Protocol for the Prohibition of the Use of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare. The U.S. reliance on this justification can be seen in the draft submitted to Congress by the Obama Administration regarding authorisation for the use of U.S. Armed force in Syria. The preamble of the draft reads:

The objective of the United States’ use of military force in connection with this authorisation should be to deter, disrupt, prevent, and degrade the potential for, future uses of chemical weapons or other weapons of mass destruction

It has been further asserted that the use of force in such a case is justified as the prohibition on the use of chemical weapons is a jus cogens norm. The problem with this however is that using force to enforce international obligations would amount to a forcible reprisal, which is also widely accepted as prohibited under international law.

In conclusion, when the U.S.-led intervention began in 2014, several legal grounds were put forward to justify it. An assessment of the justifications, particularly in light of the impending defeat of ISIS (in Syria), however shows that there is no legal basis for the U.S.-led intervention in Syria. With the impending defeat of ISIS, the United States must seriously consider the option to withdraw – even if it would involve making tough choices about a regime that it refuses to recognise. The challenge now is to take cognisance of the continued violation of international law and remedy it while the opportunity still exists.