Immanuel Kant is widely recognized as the father of modern international legal institutions like the United Nations, but international law, according to Kant, must rest on a federation of free states -- that is, what are now understood to be liberal democracies. Domestic order based on respect for individual rights and international peace are for him tightly interconnected; a proper federation would therefore look more like NATO than the United Nations. The author of this thoughtful book argues that contemporary international law is based on formal sovereignty that makes states, regardless of the type of regime or its respect for individual rights, the ultimate arbiters of justice within their borders and the final representatives of their people abroad. But with the rise of new democracies, it is possible to recast international law on a truly Kantian basis, altering the legal grounds for intervention and making the boundaries between domestic and international affairs much more porous. While Teson's views are not likely to be adopted by the international legal community any time soon, they have a powerful logic behind them.