President Bush has ordered plans for temporarily disabling the U.S. network of GPS during a national crisis to prevent terrorists from using the navigational technology, the White House said Wednesday.
Any shutdown of the network inside the United States would come under only the most remarkable circumstances, said a Bush administration official who spoke to a small group of reporters at the White House on condition of anonymity.
The GPS system is vital to commercial aviation and marine shipping.
The president also instructed the Defense Department to develop plans to disable, in certain areas, an enemy’s access to the U.S. navigational satellites and to similar systems operated by others. The European Union is developing a $4.8 billion program, called Galileo.
The military increasingly uses GPS technology to move troops across large areas and direct bombs and missiles. Any government-ordered shutdown or jamming of the GPS satellites would be done in ways to limit disruptions to navigation and related systems outside the affected area, the White House said.
President Clinton abandoned the practice in May 2000 of deliberately degrading the accuracy of civilian navigation signals, a technique known as “selective availability.”
The White House said it will not reinstate that practice, but said the president could decide to disable parts of the network for national security purposes.
The directives to the Defense Department and the Homeland Security Department were part of a space policy that Bush signed this month. It designates the GPS network as a critical infrastructure for the U.S. government. Part of the new policy is classified; other parts were disclosed Wednesday.
The White House said the policies were aimed at improving the stability and performance of the U.S. navigation system, which Bush pledged will continue to be made available for free.
The U.S. network is comprised of more than two dozen satellites that act as beacons, sending location-specific radio signals that are recognized by devices popular with motorists, hikers, pilots and sailors.