WASHINGTON - The US military shot down a target ballistic missile over the Pacific on Friday in the widest test of its emerging anti-missile shield in 18 months, the Defence Department announced.
The Pentagon's Missile Defence Agency said it had successfully completed an important exercise involving the launch of an improved ground-based interceptor missile designed to protect the United States against a limited long-range ballistic missile attack.
The results will help improve the performance of a multibillion-dollar shield against an attack that could target a US city with a weapon of mass destruction, the agency said in a statement.
Officially, the US$85 million ($131.31 million) test was designed to collect large amounts of data rather than shoot down the target. But in a news release sent 24 minutes after the intercept, air force Lt. Gen. Henry Obering, the Pentagon's missile-defence chief declared it a success, apparently even before the data could be analysed.
Philip Coyle, the Pentagon's chief weapons tester under President Bill Clinton from 1994 to 2001 and a leading critic of the Missile Defence Agency, said reviewing such data normally takes weeks.
"So it seems odd that the MDA is declaring success so soon," he said in a telephone interview with Reuters. "It makes you wonder how serious they are about the primary purpose of the test."
Other critics have accused the agency of trying to lower expectations, given glitches that have hurt the ground-based system's track record when intercepts were officially declared the chief objective.
This was the first exercise involving a mock warhead target since interceptor rockets failed to leave their silos during tests in December 2004 and February 2005.
It was also the first since the ground-based system, part of a layered shield that also includes sea- and space-based components, was activated to guard against ballistic missiles test-fired on July 4 and 5 by North Korea.
Boeing Co. is prime contractor for the ground-based mid-course defence. Major subcontractors include Lockheed Martin Corp, Northrop Grumman Corp and Raytheon Co.
In the test Friday, a target missile was launched from Kodiak, Alaska. For the first time, the ground-based interceptor missile was launched from Vandenberg Air Force Base in central California. Previous launches have been from the Kwajalein Atoll in the Marshall Islands.
Although an intercept had been said to be a possibility, the main goal had been "to collect data on overall system performance and interceptor sensor technology," said Richard Lehner, a spokesman for the Pentagon's Missile Defence Agency.
In the nine or 10 full-fledged flight intercept tests to date, depending on how one counts them, only five have shot down target missiles. Still, Obering, head of the Missile Defence Agency, has said he is confident the shield would have worked against a US-bound North Korean missile if a decision had been made to shoot it down.
President George W Bush in 2002 announced the United States would start operating the initial elements of a missile defence system by the end of 2004 to defend against a limited attack from a country like North Korea or Iran.
Since then, US missile defence spending has risen to nearly US$10 billion a year, the Pentagon's single biggest annual outlay to develop a weapons system.