Following the Sept. 11, 2001 terrorist attacks, psychologist and U.S. Air Force veteran Dr. James Mitchell was called back to national service. Along with a partner, Bruce Jessen, he was tasked with developing the CIA’s enhanced interrogation techniques, or EITs. Designed to elicit time-sensitive intelligence from hardened al Qaeda leaders, the EITs later became immersed in controversy. In 2014, Senate Democrats released a report accusing Mitchell of torturing suspects with EITs and producing no results. In his new book, Enhanced Interrogation, Mitchell offers his own testimony on the EITs. He argues that the techniques were critical in saving the lives...