Video released Wednesday shows the mid-air collision between a ground-based interceptor launched from Southern California and a simulated warhead fired from the Pacific Ocean.
The test, the first of its kind in nearly three years, was designed to prepare for any North Korean intercontinental ballistic missile strike and marked a key milestone in the U.S. missile defense system's development. The interceptor was launched from Vandenberg AFB at midday and targeted a simulated incoming warhead launched from the central Pacific Ocean.
The interceptor struck the simulated ICBM, launched from a test range on Kwajalein Atoll in the Pacific, as it traveled outside the Earth's atmosphere. Video released Wednesday by the U.S. Missile Defense Agency shows both launches and the impact.
The test was planned amid what are regarded as provocations by North Korea, which, as of last week, has carried out three missile tests in three weeks. The most recent North Korean test involved a short-range ballistic missile that traveled about 250 miles before splashing down in Japan's "exclusive economic zone" near the coast.
North Korean leader Kim Jong Un has vowed to deploy a nuclear-armed missile capable of reaching American territory. The North Koreans have not yet tested an intercontinental ballistic missile.
The American 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. A test failure would have raised new questions about the defensive system, but wasn't likely to compel the Pentagon to abandon expansion plans.
The Pentagon is still incorporating engineering upgrades to a missile interceptor that has yet to be fully tested in realistic conditions.
The U.S. defense system has roots in President Ronald Reagan's efforts to develop a response to ballistic missile threats during the Cold War, when tensions were high between the U.S. and Soviet Union. It has been in place since 2004 and never used in combat or fully tested.
The U.S. has interceptors based at Fort Greely in Alaska and four at Vandenberg AFB, about 170 miles northwest of Los Angeles.