Although many Americans anticipated swift military retaliation, little is likely to happen until satellites scan hundreds of thousands of square miles of Afghanistan's rugged terrain. "We have to have a feel for the terrain and for the weather, which we provide with our satellites, and we have to have a feeling for the weapons that potentially could be employed," says Rear Adm. James McArthur, director of operations for US Space Command at Peterson Air Force Base in Colorado Springs.
McArthur says the space technology in use over Afghanistan is a dramatic improvement from that used in the Gulf War. New satellites can process information at much faster speeds and allow ground forces to have up-to-the-moment information.
Also, missiles now are guided by satellites, which makes them more accurate than the laser-guided strikes in Kosovo just two years ago.
The satellites cannot distinguish a face or tell the difference between Bin Laden's group and a group of refugees. So they are supported by U-2 spy planes, which can use radar to detect ground movements, and unma-nned drones that take high-resolution images that reveal differences in groups of people.
Critics say Bin Laden can avoid detection by hiding in the mountains of Afghanistan and avoiding use of electronic transmissions. After learning that US spy satellites monitored his cellphone, Bin Laden reportedly reverted to low-tech personal couriers. But experts say that if Bin Laden's group moves or uses a simple handheld radio, the network of satellites and spy planes eventually will track it down.
Consequently, protecting the satellites' ground stations against terrorist attack has assumed new importance.
While the US has unsurpassed superiority in space, its satellites have an Achilles' heel. The sophisticated system, said to be capable of seeing a man tying his shoelaces, is vulnerable to a simple terrorist attack, experts say.
Terrorist groups are probably incapable of knocking out satellites in orbit, but several of the ground stations, which control the satellites, are open targets. "The ground stations are too big to hide, and they are relatively well-known," says John Pike, a national security expert. An official of the National Reconnaissance Office, which operates the US spy satellite system, declined to comment on the stations’ vulnerability. "We take the necessary steps to protect our assets,” he said.