Conforming Instrumentalists: Why the USA and the United Kingdom Joined the 1949 Geneva Conventions

Why have major Western powers committed to international laws of war? Given recent American conduct amid the War on Terror, lively debate rages over this important question in scholarly and policy circles, featuring arguments that range from sheer hypocrisy and self-interest to domestic politics and international social pressures. Through a careful study of the British and American process of deciding whether to sign and ratify the core modern law-of-war treaties – the Geneva Conventions of 1949 – and to do so with or without reservations, this article demonstrates that international social conformity pressures and instrumental motives jointly influenced these countries’ signature and ratification decisions. American and British reasoning was neither as self-serving as some realists presume nor as aloof to international social dynamics as rational institutionalist and liberal scholars commonly allow. The article calls for the further refinement of the theoretical debate on state commitment to international law of humane conduct, including humanitarian and human rights law, and encourages the pursuit of alternative methods, namely archival sources, to answer these and other enduring puzzles.