The legality of foreign military action against Islamic State in Syria

The Islamic State of Iraq and the Levant (ISIL) (also known as Da’esh) emerged in Iraq and Syria in 2013, adopting an extremely radical ideology and controlling a wide area of both the Iraqi and Syrian territories. The international community has unanimously agreed that ISIL represents an unprecedented threat to international peace and security. In October 2014, the President of the United States (US) announced the formation of an international coalition to defeat ISIL. The US-led coalition began its operations by conducting strikes in the Syrian territory. Meanwhile, the Russian air force and the Iranian Revolutionary Guard were the strongest supporters of the Assad regime in Syria. This project seeks to analyse the legal basis used to justify the use of foreign force against ISIL in Syria. The unsolicited armed action of foreign forces in Syria based on the invoked principle of self-defence as a justification is untenable in international law. The participants in the military operations in Syria have invoked different legal approaches to justify their operations. Many different questions have been raised concerning the legality of intervention with or without the consent of the Syrian government. The adoption of the self-defence principle according to Article 51 of the United Nations (UN) Charter does not provide a solid legal basis for intervention. As the international law does not give a clear answer on how to respond to armed attacks conducted by non-state actors emanating from foreign territories without the involvement of the state that harbours them. The language of the UN Security Council Resolution 2249 is controversial, as it does not explicitly authorise the use of force. The intervention by the Russian and Iranian forces, at Syria’s invitation, also faces certain legal challenges. The legality of interfering in a civil war, as well as an examination of the intervening states’ intentions and purposes, has exposed the difficulties that arise regarding respect for the fundamental principles of self-determination and intervention under international law. The ambiguity in the international law that is controlling the use of force, especially against non-state actors, as well as the lack of political consensus between the superpower states, reflects negatively on the endorsement of a mutual legal basis to eradicate the threat of ISIL and reduce the suffering of the Syrian people. As a matter of law, the consent of the Syrian Government is deemed crucial to legalise the use of force in its territory.