This paper responds to a provocative essay by Curtis Bradley and Mitu Gulati on exiting from customary international law. Bradley and Gulati argue that until the mid-twentieth century, unilateral exit from customary international law was widely accepted in at least some circumstances, and that such exit is normatively desirable. I attempt to illuminate their thesis by demonstrating the diversities of customary international law and how exit works in different categories and before different fora.

Paul B. Stephan, Disaggregating Customary International Law, 21 Duke Journal of Comparative & International Law, 191–205 (2010).