The United States provided safe harbor for decades for mass-murderer warlords who tortured, raped and cannibalized their countrymen in West Africa before settling in America alongside their victims’ relatives. Upon ransacking Liberia in civil wars that left approximately 250,000 people dead in the 1990s and 2000s, the violent war criminals sought shelter in the U.S. and hid among refugees that had been forced to flee. The warlords took advantage of Americans’ generosity and the federal government’s immigration policies and procedures to pursue the American Dream without, in many cases, even bothering to conceal their identities. In various cases, the warlords’...