History is replete with cases of intentional, systematic, and substantial destruction of noncombant civilians by powerful elites including dictatorial and nondictatorial governments and nonstate groups (e.g., rebel, militia, and terrorist organizations). In just the last 120 years, some 200 mass atrocities have occurred in which at least 100 million civilians have been intentionally killed (and likely at least half of a billion people killed, injured, or traumatized) by political leaders and their fellow perpetrators (Anderton and Brauer, 2018).