Who Has the Right to Fight? Rethinking Legitimate Authority in War

This article develops a Razian account of legitimate authority in war. It rejects the traditionalist assumption that legitimate authority is confined to states and state‐like groups while defending the criterion as a distinct and morally significant element of the jus ad bellum against revisionism. I argue that legitimate authority grounds a presumptive obligation of deference because it enables individuals to better conform to the reasons that apply to them under the conditions of epistemic uncertainty and collective action that characterise war. Drawing on Joseph Raz's service conception of authority, I identify three individually necessary conditions that constitute the minimum threshold for legitimate authority in war: knowability to those subject to authority, epistemic competence concerning the resort to and conduct of war, and sufficient institutional capacity to coordinate collective action. States that fail to meet these conditions lack legitimate authority, whereas non‐state actors that satisfy them may possess it.