Airstrikes in Syria: Are They Legal?

What occurred?

In the early hours of the morning of April Saturday 14th the United States, Britain and France made coordinated strikes on a number of alleged chemical weapons facilities on Syrian territory. US president Donald Trump announced the air strike campaign, saying, “[t]he nations of Britain, France, and the United States of America have marshalled their righteous power against barbarism and brutality[.]” The barbarism referred to is the alleged use of chemical weapons by the Syrian government in Douma last week, to which the strikes were a response. The US military gave a press conference elaborating that two chemical storage sites in the northern city of Homs and a scientific research site in Damascus had been targeted. Unverified reports have also surfaced from both within Syria and various NGOs alleging that a number of other targets were also hit.

Of the 105 missiles fired, Russia claimed that 71 were shot down by Syrian forces while the remainder hit their targets. Evidence of the impact of the strikes is yet to come to light, however both Syria and Russia have claimed that no deaths have occurred. However, immediately following the strikes it was reported that three persons were injured in Homs. The scale of the operation was approximately double that of the air strikes that were initiated in response to the use of chemical weapons in Khan Sheikhoun in April of last year.

How has the Coalition justified such a use of force?

The nations involved in the campaign have justified resorting to the use of force in two ways.

Firstly, British Prime Minister Theresa May stated that the use of force was aimed at “deterring the Syrian regime,” elaborating that the strikes would have a broader effect in deterring anyone that “believes they can use chemical weapons with impunity.” The British decision to become involved in the bombing campaign appears hinged upon this, solely aimed at ensuring compliance with the Chemical Weapons Convention. May justified the approach taken to achieving this end by claiming that there was “no practicable alternative to the use of force.” She further stated that British involvement was not aimed at regime change or attempting to support a particular side within the Syrian conflict.

Secondly, the argument has been put forth that the strikes were a measure taken in order to alleviate humanitarian suffering. This justification is related to the first, however rather than focusing on the act of using chemical weapons, it focuses on the effect chemical weapons attacks have had and the responsibility of the international community to protect the Syrian people. All three countries have released legal statements elaborating upon how the strikes were necessary and proportionate in protecting the people of Syria from breaches of the international law principle of humanity.

How has Syria and Its Allies Responded?

Sana, Syria’s state news agency, quickly asserted that the west had no legal ground to resort to the use of force against the Syrian government, labelling the attack as “a flagrant violation of international law.” Immediately following the strikes Russia moved to have the UN Security Council make a condemnation, however the resolution gained little support, with only China and Bolivia voting in favour with Russia. Russia’s ambassador to the UN, Vassily Nebenzia, cited that the west had acted before the conclusion of the investigation into the Douma chemical weapons attack in asserting that the countries involved demonstrated a “blatant disregard for international law.”


Despite justifications put forth by the governments of the United States, Britain and France, it is unlikely for any of them to provide clear authorization for use of force under international law. The main reason for this is made clear by a statement from Marc Weller, a professor of international law at Cambridge University:

“Legally, the claim to enforce international law on chemical weapons by violent means would return the world to the era before the advent of the UN Charter.”

Exceptions to the general prohibition of the use of force in the UN Charter exist, including self-defence, collective security and, contentiously, protection of a people threatened by their own government. However, for force to be exercised under these circumstances the Security Council must issue a mandate authorizing its use. The quote above makes reference to the absence of a mandate supporting the strikes, meaning that the Coalition acted outside of established international law frameworks in respect to exercising force.

The countries involved justify this with the claim that the attainment of such a mandate was not possible due to the likely exercise of Russia’s veto power. This statement is realistic, however the veto power arguably exists in the first place in order to prevent escalation between great powers. UN Secretary General Antonio Guterres has acknowledged the threat of Syria to international peace, however also emphasized that states must resign themselves to the primacy of the Security Council. In other words, no support was given for the use of force without mandate.

The argument that the Coalition had legal recourse to enforce the Chemical Weapons Convention by force is therefore weak. However, state practice in Iraq, Sierra Leone and Liberia lends some support to intervention on humanitarian grounds by states alone. It is established doctrine of international law that the international community may intervene in exceptional circumstances in order to protect a population from atrocities perpetrated within a sovereign nation. However, this doctrine is largely considered to only give authorization for operations undertaken by means of Security Council mandate. Intervention outside of mandate is only regarded as valid by a small number of countries.

Syrian sources have suggested that the actions of the coalition may be punishable under the crime of aggression, however in light of the rejection of the previously mentioned Russian resolution this is unlikely to gain sufficient political traction.


The recent coalition airstrikes in Syria are legally questionable due to the absence of a Security Council mandate. This sheds light on the conflict between protecting a civilian population from harm and maintaining international peace and security. The veto power,  which has prevented continuous resolutions on alleged uses of chemical weapons, is designed to prevent escalation between great powers, however it is sometimes regarded to sacrifice the capacity to protect populations from grave breaches of human rights. The actions of the coalition appear to breach established constraints placed upon the use of force, demonstrating disregard for international law. This erodes the validity of such law, perhaps encouraging instability, and furthermore sets a poor evidentiary standard for intervention, evidenced by the occurrence of strikes prior to the conclusion of relevant investigations.