What Can the NSA Do Anyway?

Can the National Security Agency listen to your cell phone calls? You bet.

Around the world, if you are communicating electronically -- e-mails, faxes, telephone calls, cell phone calls, BlackBerries -- the NSA may be listening with satellites 22,000 miles in space, submarines tapping into fiber-optic cables at the bottom of the ocean, enormous Boeing 707s packed with eavesdropping gear, and major listening centers. There are two listening centers in the United States -- in Yakima, Wash., and Etam, W.Va.

"An average listening post picks up about a million communications per half hour," said James Bamford, author of "Body of Secrets," which is about the NSA.

A call placed from overseas to, say, Atlanta, would be beamed down from a satellite to an AT&T call center. A few miles away, the NSA would be collecting the data.

At NSA headquarters in Maryland, enormous computers plow through that data searching for phone numbers, names, even words.

"If you pick the word 'jihad' out of a conversation, the technology exists that you focus in on that conversation and you pull it out of the system with the processing," former NSA employee Russ Tice said.

Tice is prepared to tell Congress all he knows about the alleged wrongdoing in "special access programs" run by the Defense Department and the NSA in the post-9/11 efforts to go after terrorists.

Analysts often use that information as a starting point, seeing, for instance, if bank withdrawals line up with anyone else's deposits.

President Bush will visit the NSA today.

The NSA would not let ABC News anywhere near its headquarters; it has been so secretive for so long that it's been joked that its initials stand for No Such Agency. But with questions about the legality of its eavesdropping program, the NSA is cutting a much larger profile these days.