Five years ago, Congress killed an experimental Pentagon antiterrorism program meant to vacuum up electronic data about people in the U.S. to search for suspicious patterns. Opponents called it too broad an intrusion on Americans' privacy, even after the Sept. 11 terrorist attacks.
But the data-sifting effort didn't disappear. The National Security Agency, once confined to foreign surveillance, has been building essentially the same system.
NSA gets access to the flow of data from telecommunications switches through the FBI, according to current and former officials. It also has a partnership with FBI's Digital Collection system, providing access to Internet providers and other companies. The existence of a shadow hub to copy information about AT&T Corp. telecommunications in San Francisco is alleged in a lawsuit against AT&T filed by the civil-liberties group Electronic Frontier Foundation, based on documents provided by a former AT&T official. In that lawsuit, a former technology adviser to the Federal Communications Commission says in a sworn declaration that there could be 15 to 20 such operations around the country.