The ban on war in the UN Charter is often celebrated for restricting the reasons that governments can go to war. But those limits are also empowering for governments: the Charter authorizes governments to use force in self-defense, and they have shown themselves eager to make use of that authority. This facilitates the use of force by states rather than limiting it.

By creating the legal category of 'self-defense,' international law gives to states an iron-clad legal rationale to legitimate their wars. And over time, the category has expanded as powerful states have used it to justify ever broader military interventions in the world. My new article shows the permissive power of international law on war and suggests that the ban on war may make it easier, not harder, for governments to go to war.

Ian Hurd, "The Permissive Power of the Ban on War," European Journal of International Security, August 2016, pp.1-18. pdf here and website