A ground-based interceptor launched Tuesday from Southern California's Vandenberg Air Force Base shot down a simulated incoming warhead as part of a U.S. defense system test.

The drill at the Santa Barbara County base was designed to prepare for any North Korean intercontinental ballistic missile strike and marked an important milestone in the 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 test launch, the first of its kind in nearly three years, was seen from miles away, but the missile intercept was not visible, according to the air base. The interceptor struck the mock warhead as it traveled outside the Earth's atmosphere.

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.

A rocket soars into space, then releases what officials call a "kill vehicle" equipped with a system that guides it into the path of a missile. The interceptor launched Tuesday from Vandenberg AFB targeted a simulated ICBM launched from a test range on Kwajalein Atoll in the Pacific. The simulated missile flew faster that those used in previous ground-based interceptor tests.

"This is the first test event against an ICBM-class target for the ground-based mid-course defense system," said Navy Capt. Jeff Davis. "Program officials will evaluate system performance based upon telemetry and other data obtained during the test."

In a statement, Davis said the test was not timed due to recent actions by North Korea, but that the country is one of the reasons the U.S. is testing the system's capability.

"North Korea has expanded the size and the sophistication of its ballistic missile forces from close-range ballistic missiles to intercontinental ballistic missiles," Davis said. "They continue to conduct test launches, as we saw even this weekend, while also using dangerous rhetoric that suggests that they would strike the United States homeland."

The U.S. has interceptors based at Fort Greely in Alaska and four at Vandenberg AFB, about 170 miles northwest of Los Angeles.

Earlier this month, an unarmed intercontinental ballistic missile was launched from Vandenberg Air Force Base as part of a test. The Minuteman III missile launch lit up the night sky and soared about 4,200 miles to a test range near the Kwajalein Atoll in the Marshall Islands.



In its 2018 budget presented to Congress last week, the Pentagon proposed spending $7.9 billion on missile defense, including $1.5 billion for the ground-based mid-course defense program. Other elements of that effort include the Patriot designed to shoot down short-range ballistic missiles and the Terminal High-Altitude Area Defense, or THAAD, which the U.S. has installed in South Korea as defense against medium-range North Korean missiles.

The Trump administration has yet to announce its intentions on missile defense.

President Trump recently ordered the Pentagon to undertake a ballistic missile defense review. Some experts argue the current strategy for shooting down ICBM-range missiles, focused on the silo-based interceptors, is overly expensive and inadequate. They say a more fruitful approach would be to destroy or disable such missiles before they can be launched, possibly by cyberattack.

City News Service contributed to this report.