The Permissive Power of the Ban on War
This chapter examines a classical area of international law: the use of force by states. The ban on war is often cited as the centerpiece of the modern international legal-political system and used to distinguish the contemporary age from earlier, less legalized periods. Liberal convention sees the ban on war as a legal constraint on states' political choices; states seeking to uphold the international rule of law are advised to refrain from using force against other states. However, this understanding is flawed. The UN Charter outlaws some kinds of war and permits others, such as those undertaken in self-defense. The chapter then demonstrates that the Charter is a mechanism by which law sorts the motivations for war into lawful (self-defense) and unlawful (all others) categories. It thereby creates a framework to legitimate wars and reduce their political costs. The Charter is not antiwar: it is explicitly permissive of war so long as the claimed motive is self-defense.