For those who hold that Kant pared down and modernized the laws of war, §60 of the ‘Doctrine of Right’ on the ‘unjust enemy’ is a continuing provocation. Does not Kant state there that the ‘injustice’ of an opponent is sufficient cause for waging preventive war and for staging aggressive interventions? Does he not argue that the rules of war can be suspended, that like-minded states can pool their resources to attack an unsuspecting outsider, and that domestic as well as international constitutionalism can be imposed by an external force? In response to such interpretations, Howard Williams has suggested the passage is fundamentally ironic, and the notion of an unjust enemy effectively inapplicable. This chapter proposes an alternative reading. First, it explains the function of §60 in the architecture of the ‘Doctrine of Right’ as a transitional provision between natural and public international law and shows that its normativity is restricted to a state of nature among states. In a second step, it attempts to show that, for Kant, the incriminated passage concerns exclusively the ius in bello and ius post bellum, not the ius ad bellum. The passage delineates permissible aims and powers in a war of self-defense, and the ways in which they may contribute in establishing a lasting peace. In a third step, the chapter criticizes the political uses much recent Kant literature has made of the passage and discusses more plausible historical examples to which the category may be applied.