The Puzzle Palace
The Puzzle Palace is a book written by James Bamford and published in 1982. It is the first major, popular work devoted entirely to the history and workings of the National Security Agency, a United States intelligence organization. The title refers to a nickname for the NSA, which is headquartered in Fort Meade, Maryland. In addition to describing the role of the NSA and explaining how it was organized, the book exposed details of a massive eavesdropping operation called Operation Shamrock. According to security expert Bruce Schneier the book was popular within the NSA itself, because "the agency's secrecy prevents its employees from knowing much about their own history".
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Before the book's publication, the Reagan administration claimed that unclassified source documents were released to Bamford in error, and threatened him with prosecution if he did not return 250 pages of documents he had obtained through Freedom of Information Act (FOIA) requests. The documents in question related to a 1975-76 Department of Justice investigation, and described the NSA's widespread illegal monitoring of domestic communication, warrantless surveillance of Americans, and monitoring of commercial cable and telex traffic
http://en.wikipedia.org/wiki/The_Puzzle_Palace