WASHINGTON ( CNN ) -- A missile shield test was a `` smashing success , '' Pentagon officials said Friday , despite the failure of the test to put to rest concerns that the interceptor might not be able to differentiate between real missiles and decoys . Eight of the United States ' 13 missile defense tests have been deemed a success . The ground-based interceptor missile , launched from Vandenberg Air Force Base in California , destroyed a long-range ballistic missile launched from Kodiak , Alaska , the Defense Department 's Missile Defense Agency said . But one key aspect of the test -- to see whether the system could tell the difference between a missile and a decoy aimed at confounding its `` seek '' systems -- failed because the decoy did not deploy . Officials told CNN on Thursday that Friday 's test would be the most realistic of 13 missile shield system tests conducted to date . Eight of the 13 tests have now been deemed a success by the Pentagon . Watch a Pentagon spokesman explain the Friday 's problem » . This was the first test in which a crew at an alternate fire control center in Alaska remotely launched the interceptor missile from California . The `` initial indications , '' according to the Defense Department , are that all components of Friday 's test performed as designed . Critics have long complained that the tests are not realistic because they do n't involve balloons or other simple decoys that , they argue , could easily fool the interceptor . Watch a report on the defense system » . In Friday 's test , however , the target was a mock warhead and was supposed to be accompanied by `` countermeasures similar to what Iran or North Korea could deploy , '' according to a missile defense agency official . The intention was for the interceptor 's kill vehicle to distinguish the target from the decoys . But the decoy that was supposed to deploy to test the system did not . The Pentagon blamed a 40-year-old target system . `` Countermeasures are very difficult to deploy . We have had trouble deploying them in the past , '' said Lt. Gen. Patrick J. O'Reilly , director for the Missile Defense Agency . But O'Reilly said that the interceptor did differentiate between the actual missile target and the upper stage of the missile it had detached from . The test , which had been delayed several times , comes at a crucial time for the $ 100 billion system , as President-elect Barack Obama is about to take office . Early in his campaign , Obama pledged to `` cut investments in unproven missile defense systems . '' But he later said he would support missile defense systems if they work . `` The biggest threat to the United States is a terrorist getting their hands on nuclear weapons , '' Obama said in the September 26 presidential debate . `` And we are spending billions of dollars on missile defense . And I actually believe that we need missile defense , because of Iran and North Korea and the potential for them to obtain or to launch nuclear weapons . '' Friday 's test also showed the Pentagon that multiple sensor systems were able to network together and hone in on a single object , O'Reilly said . `` All those sensors working together , at any one time the system knew which sensor was reporting what and tracking it and gave the war fighter one presentation of a target , '' O'Reilly said soon after the test was finished . `` That was one tremendous accomplishment for us . '' Last month , the outgoing head of the Missile Defense Agency said that not only are U.S. missile defenses workable , they are up and running . `` Our testing has shown not only can we hit a bullet with a bullet , we can hit a spot on the bullet with a bullet . The technology has caught up , '' Lt. Gen. Trey Obering said . CNN 's Jamie McIntyre and Adam Levine contributed to this report .
NEW : `` Countermeasures '' failed to deploy during test . Missile launched from Alaska ; interceptor launched from California . Shield critics have long complained previous tests did n't involve decoys . President-elect Obama has said he 'll support missile defense systems if they work .