(WASHINGTON) -- Three straight failed tests of missile defense interceptors haven't shaken the Pentagon's confidence in its ability to defend the U.S. against the threat of a long-range missile strike by North Korea, a military spokesman said Monday.
A Ground-based Midcourse Defense interceptor launched Friday from Vandenberg Air Force Base in California failed to strike a test Intercontinental Ballistic Missile (ICBM) launched from Kwajalein Atoll, in the Marshall Islands.
The test was designed to simulate an incoming ICBM targeting the West Coast with an intercept to have occurred over the Pacific Ocean.
While two previous failed tests involved newer versions of the targeting system, the failure Friday involved the targeting system used by the 30 interceptors currently deployed at Fort Greeley, Alaska, and at Vandenberg.
The mid-course interceptor is part of the integrated missile defense network that includes targeting radar, as well as layered interceptors that can strike an incoming missile shortly after launch or as it approaches its final target.
Pentagon spokesman George Little said the failed intercept had raised concerns, but not enough to discount the missile defense system's ability to protect against a North Korean long range missile threat.
"We believe that we have a robust missile defense architecture in place and we are in a position to respond to any threat that emanates from North Korea," Little said.
"Our faith in our missile defense program remains strong and every healthy organization takes stock of mishaps when they occur and that's what we're doing now," he said.
Some analysts, however, say the intercept failure raises concerns.
"The reliability of our missile defense system is being brought into question," said Charles Vick, senior technical and space policy analyst at globalsecurity.org. "The technology is still being perfected, and the level of reliability is not up to necessary standards."
Little said there may be some overreaction to the test results, and that despite the legitimate concerns raised, the Pentagon is "committed" to the program.
"I wouldn't draw any broad conclusions based on one test," Little said. "I understand the concerns here. We're concerned, too."
"We remain committed to our missile defense program and I think that we'll be looking at the root causes of what happened on the fifth [Friday] and take steps to ensure that similar failures don't occur in the future," he said.
So far, the ground based interceptors have hit their targets in eight out of 16 intercept tests, with the last successful intercept in December 2008.
Rikki Ellison of the Missile Defense Advocacy Alliance said he believes the system is viable, though the failed intercept "reduced confidence and reliability" in defending against a North Korean missile attack.
Both Vick and Ellison said the end result of the failed intercept will be that multiple interceptors will have to be used against a single incoming warhead to ensure success, which could reduce the current inventory of missiles and limit further capability.
"We must have the fortitude to fix the issues that caused the failures quickly, soundly and as soon as possible," Ellison said. "This system is all our nation has today to stop and intercept long-range nuclear missiles. We have to have it."
The type of missile interceptor that failed to hits its target in Friday's test was similar to the 30 interceptors currently in operation to protect the West Coast from an incoming ICBM missile attack, presumably from North Korea.
There are 26 of the missiles deployed at Fort Greeley and an additional four at Vandenberg AFB. In March, the Obama administration announced that it would add 14 more of the interceptors.
Little said on Monday he did not know of any impact the failed missile intercept might have on the planned expansion.
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