February 2021 American airstrikes in Syria: necessary and proportionate acts of self-defence or unlawful armed reprisals?

ABSTRACT This article examines the jus ad bellum necessity and proportionality requirements pertaining to the American airstrikes on 25 February 2021 against alleged Iran-supported non-state militia groups in Syria. From the limited publicly available information, the February airstrikes appear to be punitive rather than defensive. Consequently, this author concludes that the airstrikes were likely unnecessary as there was no situation of genuine emergency that required the USA to act when and where it did or else lose the ability to defend itself effectively. The necessity of targeting the militiamen in Syrian territory is also highly questionable. If not necessary, the airstrikes constitute unlawful armed reprisals. The proportionality of the airstrikes is moot, therefore, although the article proceeds to articulate certain challenges to assessing such proportionality if the necessity of the American response against an ongoing threat could be hypothetically established.