David Scheffer is the former Mayer Brown/Robert A. Helman Professor of Law at Northwestern Pritzker School of Law (2006-2020). He was the U.S. Ambassador at Large for War Crimes Issues (1997-2001) and led the U.S. delegation to U.N. talks to establish the International Criminal Court. He is Vice President of the American Society of International Law and visiting senior fellow at the Council on Foreign Relations. His latest book is The Sit Room: In the Theater of War and Peace (Oxford 2019).