Abstract

Common sense suggests that if a war is unjust, then there is a strong moral reason not to contribute to it. I argue that this presumption is mistaken. It can be permissible to contribute to an unjust war because, in general, whether it is permissible to perform an act often depends on the alternatives available to the actor. The relevant alternatives available to a government waging a war differ systematically from the relevant alternatives available to individuals in a position to contribute to the war. Hence the conditions determining whether it is permissible for a government to wage a war often differ from the conditions determining whether it is permissible for others to promote that war. This difference is manifest most often in unjust wars with putatively humanitarian aims—an increasingly common type of war