WASHINGTON — President Bush on Tuesday ordered the Pentagon to deploy a rudimentary missile defense system as early as 2004, placing interceptor missiles in Alaska and, in a surprise move, also at Vandenberg Air Force Base in Southern California.
"The new strategic challenges of the 21st century require us to think differently, but they also require us to act," Bush said in a statement. "The deployment of missile defenses is an essential element of our broader efforts to transform our defense and deterrence policies and capabilities to meet the new threats we face."
Critics in Congress and the scientific community denounced the move as an effort to put a missile defense system in place despite unresolved questions about its purpose and reliability.
Administration officials denied that the decision to deploy a missile defense system while it was still in the testing phase was in reaction to North Korea's announcement last week that it would resume its nuclear program. But when pressed, officials acknowledged that one intention of the early deployment was to deter attacks from potential enemies.
"We do think that missile defense capabilities can have a powerful impact on those countries that might threaten us," said J. D. Crouch, assistant secretary of Defense for international security policy. "They have a deterrent effect, and we hope they have a dissuasive effect."
Pentagon officials said they would request additional funding of $1.5 billion over two years to pay for the deployment -- a request that Congress is expected to approve. That would be in addition to the $8 billion the Pentagon receives annually for its missile defense program.
Defense Secretary Donald H. Rumsfeld said that theoretically, all 50 states would be protected by the preliminary system, but that its limited size and uncertain reliability would mean it could offer only "modest" protection. Still, he said, something is better than nothing.
"It would be in a testing and learning mode," Rumsfeld told reporters. "But also, in the event it were needed, it would be able to provide you some limited capability to deal with a limited number of ballistic missiles."
Rumsfeld said the deployment would proceed despite less-than-perfect flight test results. Of eight tests to date, only five have been successful. The most recent flight test of an interceptor missile failed about a week ago.
"You have to put something in place and get knowledge about it and have experience with it, and then add to it over time," Rumsfeld said. "I mean, there isn't a single weapon system we have that hasn't gotten better successively over a period of time that I can think of."
"Test, fix. Test, fix. Test, fix is what we're doing," said Lt. Gen. Ronald Kadish, director of the missile defense program.
The interceptors consist of booster rockets that release a "kill vehicle" -- a device less than 5 feet long and weighing only about 120 pounds -- which uses sophisticated sensors to home in on enemy missiles or warheads, destroying them with the force of a collision.
During his election campaign, Bush pledged to accelerate the testing and deployment of a missile defense system. Last June, the United States abrogated the ABM treaty with Russia, which had restricted testing, in order to accelerate development of a missile defense system.
But technical difficulties have slowed progress. The Clinton administration had called for placing as many as 20 interceptors in Alaska or South Dakota by 2004. The Bush administration did not adopt that timetable, and instead had announced only that the United States would build a "test bed" of five interceptors at Ft. Greely, near Fairbanks, Alaska, in 2004.
The president's new order instead doubles the 2004 deployment to 10 missiles -- six at Ft. Greely and four at Vandenberg. In 2005, an additional 10 missiles would be installed in Alaska.
The Pentagon would continue the deployment of upgraded Patriot systems to protect against shorter-range missiles, and would place up to 20 interceptors on specially outfitted Aegis naval cruisers. Those cruisers could be deployed worldwide, providing protection to allies, the Pentagon said.
This is the first time any administration has publicly considered placement of missile defenses in California. A Pentagon official said Vandenberg was chosen because it is already a missile base with testing facilities.
"There is already infrastructure there, so it is a logical place to put them in the continental United States," the official said.
Opponents denounced the deployment as providing a false sense of security. "If putting in a system is going to prevent you from taking real steps to protect against missiles and proliferation, then this is worse than nothing," said Lisbeth Gronlund of the Union of Concerned Scientists.
At a briefing, Pentagon officials played video of missile defense tests in an effort to demonstrate that the technology is workable, if primitive.