Above the politics and ideological battles of Washington, D.C., is a committee that meets behind locked doors and leaves its paper trail in classified files. The President's Intelligence Advisory Board (PIAB) is one of the most secretive and potentially influential segments of the U.S. intelligence community. Established in 1956, the PIAB advises the president about intelligence collection, analysis, and estimates, and about the legality of foreign intelligence activities. Privileged and Confidential: The Secret History of the President's Intelligence Advisory Board is the first and only...