For seven years I have remained silent about the false claims magnifying the effectiveness of the so-called enhanced interrogation techniques like waterboarding. I have spoken only in closed government hearings, as these matters were classified. But the release last week of four Justice Department memos on interrogations allows me to shed light on the story, and on some of the lessons to be learned. One of the most striking parts of the memos is the false premises on which they are based. The first, dated August 2002, grants authorization to use harsh interrogation techniques on a high-ranking terrorist, Abu Zubaydah,...