There are many good reasons to read David Scheffer's All the Missing Souls: its insider story of the war crimes trials, written by one of their architects, the in-depth case studies on Bosnia, Rwanda, Cambodia, the impassioned defense of international justice as a moral idea. But the part I found most useful is in the post-script, where Scheffer re-articulates his theory that we need a new concept to describe the types of crimes dealt with by...