INTELLIGENCE: NSA: Inside the Puzzle Palace

The National Security Agency is like the Jorge Luis Borges fable of the infinite library in which all of the planet's knowledge and information reside, maddeningly encoded. Into the NSA's heavily guarded, three-story headquarters outside Washington every week the world's secrets flow from U.S. spy ships, surveillance planes, satellites and hundreds of electronic listening posts round the globe. Unlike the CIA and other U.S. intelligence agencies, the NSA's mission is strictly communications—electronics and cryptology. It is the ultimate bug, the source of most of the nation's foreign intelligence information and, like...