Experimental interceptor bases in Alaska and California can be made ready to fire at incoming ballistic missiles within minutes or hours, the chief of the Missile Defense Agency said Wednesday.
The comments from Lt. Gen. Henry A. Obering III in a conference call with reporters suggest the United States is technically ready to try to shoot down a few incoming intercontinental ballistic missiles with little warning.
The Bush administration has declined to declare the missile defense system operational, as it had once hoped to do by the end of last year. Nevertheless, missile defense officials describe the two bases as having an operational capability even though they are experimental in nature. The system must switch from a test mode to an operational one before it can fire, they said.
Whether it takes minutes or hours to change modes depends on how the systems are configured when the decision is made to become operational, Obering said. If the system is in the middle of a major software upgrade, it might take hours, he said.
To shorten the time, Obering said officials are installing a system in which it could be set to an operational mode almost instantaneously. He did not say when that would be completed.
Threat from North Korea?
How long it takes to ready the defenses could be critical if the United States were to face a surprise attack from North Korea, which Washington perceives as presenting the most likely near-term threat from long-range missiles.
It is not clear whether the North Koreans have the capability to put a nuclear warhead on a missile that can reach U.S. territory.
Still, such a missile launched from North Korea could reach the western United States in half an hour. Thus, given so little notice, it is not certain whether a surprise launch could be intercepted.
But missile defense officials have said they would expect some kind of strategic warning that a launch is possible, giving them some time to ready the system.
The system has mechanical blocks on the eight interceptor missiles — six in silos at Fort Greely, Alaska, and two more at Vandenberg Air Force, Calif. — that prevent them from launching. They can be removed quickly, officials said.
The system also relies on radars in Alaska, California, at sea and in orbit, and command centers in the United States.
Whether those defenses could shoot down an incoming missile is an open question. In two recent $85 million tests, the interceptors have failed to get out of the silos.
In the first, on Dec. 15, the missile did not launch because of the software that monitors the communications flow between the missile and ground controllers detected what it was programmed to perceive as too many missed messages. In response, officials set the software to be more tolerant of missed messages — a fix that amounted to changing one line of code, Obering said Wednesday.
The second test failed because an arm that holds up the interceptor did not fully retract in the moments before it launched, Obering said. The interceptor shut down automatically. Engineers do not know why the arm did not retract, he said.
Both tests involved launching an interceptor from Kwajalein Island in the Pacific Ocean at a target launched from Kodiak Island, Alaska. The Kwajalein base is for testing only.
In earlier tests, the system was successful in five of eight tests in highly scripted attempts to intercept a target missile carrying a mock warhead.
More tests are scheduled for later this year.