SPIES IN CYBERSPACE

Within seconds, billion-dollar Pentagon spy satellites can deliver detailed photographs to ground stations. The National Security Agency's supercomputers can sort through intercepted phone calls with lightning speed. Even clandestine agents overseas can have instant access to CIA officials in the U.S. by using cellular phones. But until last year, the White House had to depend on the "pizza truck " for all this intelligence--even during a fast-breaking crisis. And the pizza truck--the agency's nickname for the delivery van bearing secret reports from the CIA's Langley, Virginia, headquarters--often became snarled in downtown Washington traffic.

Now, however, the CIA and other U.S. intelligence...