The U.S. Government executed its first military intervention in Syria through the launching of airstrikes during the summer of 2014. Its course of action was a response to ISIL’s expanding territorial and political eminence in Northern Syria and shortly after, Iraq’s capital. In order to counteract ISIL’s threatening power, the U.S. formed and led a coalition with Arab allies. The coalition advised and trained Syrian Democratic Forces in order to protect American interests and put an end to the group’s harming of civilians, manipulation of foreigners to join ISIL, and the unlawful use of chemical weapons. However, there still remains uncertainty regarding the legality of such interventionist actions. International law under the UN legitimizes military intervention in pursuit of preserving international security and peace. So, if the U.S. has conducted its operations according to such premises, it may be legally justifiable. However, even if military intervention was justified according to international law, such justification would be futile without the United Nations Security Council’s authorization and Syria’s approval of the use of force in their territory.

The ambiguity inherent in the UN statute has made the matter of justification even more difficult to discern. Before accusing the Syrian regime of committing actions in violation of international law, it is important to consider how the laws themselves may be obscure and feebly enforced. Also, one must consider how this may consequently establish leeway for such laws to be applied in a manner that warrants United States military intervention. Human Rights Watch accused the Syrian regime of 85 documented chemical weapon attacks in Syria prior to 2018, and according to the OPCW, these attacks are unlawful. It states that “the use of chemical weapons is prohibited under international humanitarian law regardless of the presence of a valid military target.” Since such destruction was propagated by the Syrian government on its own people, it would constitute as a crime against humanity, which is further recognized by the rationale of the UN’s Responsibility to Protect. Its doctrine encourages nations to resolve atrocities against civilians, especially in cases where their own state is the perpetrator of such atrocities or ceases to provide such protection. Accordingly, it can be argued that if a state (like the U.S.) fails to intervene and resolve such conflict in Syria, it is not upholding its legal obligation. On the other hand, it can be argued that Assad’s employment of chemical weapons against civilians of his own state did not necessarily provide nations with the legal justification to use force as a means of attempting to resolve the conflict. This reasoning is validated in Article 2(4) of the UN Charter, which prohibits the “threat or use of force against” any member state. According to this premise, the U.S.’s use of force in the form of launching 14 airstrikes against ISIS in 2014 and 59 Tomahawk cruise missiles in 2017 would be considered a violation of international law. 

The legitimacy behind the U.S’s military action raises more questions when examining the UN’s exemptions from the rule of prohibiting the use of force and whether such exemptions apply to the U.S. The UN charter affirms two exceptions to the rule of prohibition of the use of force: The first exemption is granted based on the Security Council’s authorization and the second through self-defense. The U.S.’s rationale for exercising these exemptions may have some ethical and humanitarian merit, however, this justification could have been based on an interpretation that does not completely align with the UN charter’s legal terms or the US constitution itself. This reasoning may render their military interventions unlawful. Article 51 of the Charter permits “the inherent right of individual or collective self-defence if an armed attack occurs” in addition to certain conditions that permit the preemptive use of force against anticipated attacks. This means that Syria’s use of chemical weapons, especially if launched without warning, may hinder the U.S.’s ability to safeguard its interests, which could entitle them to use force on the grounds of self-defense. Not only is it questionable whether the chemical weapons pose a threat imminent enough to necessitate the use of force, but also whether this law’s rationale accurately applies to the real dangers occurring in Syria and not dangers that the US only perceives as a threat. The Obama administration’s justification for launching airstrikes in Syria, if solely based on this ambiguous proposition, may be in contradiction with the law. Additionally, Chapter VII of the charter permits the use of force if authorized by the UNSC “to maintain or restore international peace and security.” Yet no records prove that the Security Council ever authorized the U.S.’s launching of airstrikes in 2014, which would support the notion that their intervention was a breach of international law. 

If uncertainty exists when questioning the international lawfulness regarding the U.S.’s military action, this uncertainty may exist equally when examining its military’s lawfulness domestically (according to the American Constitution). For instance, the Trump administration’s launching of 59 missiles was conducted based on the 2001 Authorization for the Use of Military Force Resolution. Since this decision was not executed based on direct approval from Congress, it may be deemed as illegal. The AUMF only permits the US to use force against Al-Qaeda; specifically, groups who “planned, authorized, committed, or aided” the 9/11 attacks. Although ISIS is an offshoot of Al-Qaeda, the resolution’s language conveys that it is technically not the group that executed the 9/11 attacks and is not certain to be the perpetrators of the chemical weapons attack that Trump attempted to retaliate.  

The conditions that the UN declared as exceptions to the rule of prohibition from using force in another state may be applicable to the U.S. on the grounds of self-defense and upholding the principles of the UN’s ‘responsibility to protect’. However, with a doctrine that is not legally binding, an ambiguous legal framework that leads to narrow interpretation, and the failure to receive congressional approval, it can be argued that the U.S.’s military intervention in Syria is unlawful on multiple fronts. But more importantly, such pervasive ambiguity and contradictory legal agreements and terms call for a revision of the UN’s agenda in order to accurately determine the legality of U.S. intervention.