It is possible to accept Laporta’s general approach to international law, which is inspired by legal cosmopolitanism as well as by political realism, without accepting the normative conclusions he reaches drawing on such an approach. I offer a few criticisms of Laporta’s essay. Firstly, the relatively recent attempt to outlaw war does not provide a secure foundation for international law, as maintained by Laporta. The international legal regulation of war is not only contingent, but also ineffective, contradictory and uncertain. Secondly, there is no need for a theoretical foundation of international law whatsoever: if a theory of law is unable to account for the legal nature of international law, this is a good is a reason for dismissing that theory instead of denying the existence of international law. Thirdly, and most importantly, no normative conclusion —and in particular no justification of humanitarian intervention— can ever be drawn from a theoretical foundation of international law: such a justification should rely on a variety of principled and pragmatic considerations that have no bearing on the legal status of international law.