Responding to Henkin's compliance theory, Goldsmith and Posner asserted in 2005 that “rational choice” theory proves that few states ever truly “comply” with international law. What looks like compliance is pursuit of “self” interest. They conclude that violations of international law, therefore, cannot be condemned as violations of law. To apply their theory, however, they make a series of implausible assumptions and fail to incorporate developments in behavioral economics or the insights of post-modernism. Both support the importance of such human impulses as altruism and belief. And it is these that actually support the claim that international law is law and that coercive means may be used to enforce it — as was always understood in natural law theory. Reviving natural law theory to explain the basis of international law's authority can best be done by incorporating process theory and retaining the centrality of positivism.