The test, conducted over the Pacific Ocean, aims to enhance the reliability of the USA missile defense system and keep North Korea, which is developing an ICBM, in check.
A ground-based interceptor launched from Vandenberg Air Force Base in California "successfully intercepted an intercontinental ballistic missile target" fired from the Reagan Test Site in the Marshall Islands, the Pentagon announced.
Riki Ellison, founder of the Missile Defense Advocacy Alliance, described the test as "vital" prior to launch.
The U.S. interceptor has an uneven track record, having succeeded nine times out of 17 attempts against missiles in test since 1999, although the most recent test in June 2014 was a success.
In a show of strength aimed at ever-belligerent North Korea, America has shot down what it calls a "simulated ICBM" with an intercept missile.
Vice Admiral Jim Syring, director of the Pentagon's Missile Defense Agency, hailed the test as an "incredible accomplishment" in a statement.More news: Angela Merkel, minister stress U.S. ties after critical Donald Trump tweet
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"This system is vitally important to the defense of our homeland, and this test demonstrates that we have a capable, credible deterrent against a very real threat".
Last week, the Pentagon presented its 2018 budget to Congress, proposing spending 7.9 billion US dollars on missile defense, including 1.5 billion dollars for the ground-based mid-course defense program. The continental United States is about 9,000km from North Korea.
"This is part of a continuous learning curve", said Navy Capt. Jeff Davis, a Pentagon spokesman, ahead of Tuesday's test.
A successful test was by no means guaranteed and the Pentagon sought to manage expectations earlier in the day, noting that the United States had multiple ways to try to shoot down a missile from North Korea. "Today is an important day for our nation's missile defenders, our scientists and engineers, and the American people".
The Pentagon on Tuesday announced it had successfully conducted its first live-fire test against a simulated intercontinental ballistic missile capable of striking the USA mainland. With congressional support, the Pentagon is increasing by the end of this year the number of deployed interceptors, based in California and Alaska, to 44 from the current total of 36. "By successfully shooting down an ICBM-class target, America demonstrated that we can defend ourselves from nuclear attack".