Political theory can help explain elements of gross human rights violations, especially genocide. Liberalism, for example, is helpful in suggesting that liberal democracies typically do not engage in mass murder, nor do they wage war on each other. Genocides and other massive human rights violations generally have occurred during time of war. In its emphasis on the self-defeating character of war and the need for limitations on its conduct, Grotian international legal theory also is helpful. Common gains for the world's communities as the result of liberal international cooperation suggest the constitution of international regimes that would implicitly or even explicitly prohibit mass murder. International legal frameworks for such cooperation typically do just that. The European Union as a prototypical example has increasingly emphasized democracy and the protection of human rights as a condition of state membership. Utilitarianism,...