The Pentagon celebrated the first successful salvo test of an anti-missile defense system designed to shoot down nuclear-armed intercontinental missiles from enemies such as North Korea.

According to Missile Defense Agency Director Air Force Lt. Gen. Samuel Greaves, the missile defense system functioned "exactly" as intended after two ground-based interceptors, or GBIs, were launched from Vandenberg Air Force Base, Calif., on Monday to take down a mock warhead that took off 4,000 miles away.

A mock warhead took off from Reagan Test Site on Kwajalein Atoll in the Marshall Islands.

After the threat-representative intercontinental ballistic missile target launched, the GBI-Lead interceptor successfully shot down the unarmed re-entry vehicle. The second interceptor, known as the GBI Trail, then targeted the next “most lethal object” after it failed to identify any other re-entry vehicles, according to the Missile Defense Agency.

"This was the first GBI salvo intercept of a complex, threat-representative ICBM target, and it was a critical milestone," Greaves said in a statement Monday. "The system worked exactly as it was designed to do, and the results of this test provide evidence of the practicable use of the salvo doctrine within missile defense. The Ground-based Midcourse Defense 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."

Although North Korea hasn't conducted a test since late 2017, U.S. officials doubt North Korea will actually give up its nuclear weapon and missile programs. For example, Director of National Intelligence Dan Coats told the Senate in January, “We currently assess that North Korea will seek to retain its WMD [weapons of mass destruction] capabilities and is unlikely to completely give up its nuclear weapons and production capability, because its leaders ultimately view nuclear weapons as critical to regime survival.”

Late last month, President Trump walked away from a meeting with North Korean leader Kim Jong Un in Hanoi, Vietnam, dedicated to talks about denuclearization of the Korean Peninsula. Afterwards, North Korean Vice Foreign Minister Choe Son Hu warned the rogue regime would halt denuclearization discussions with the U.S. and said Kim may start conducting missile tests again.

The Missile Defense Agency's successful test Monday was lauded by Sen. Dan Sullivan, R-Ark., who said the demonstration would prompt enemies to second-guess their offensive capabilities.

"This test gives our enemies pause, making them doubt the effectiveness of their offensive capabilities," Sullivan said in a statement Monday. "This doubt, coupled with the threat of a military response from the U.S., bolsters our deterrence posture, including against threats from rogue nations.”

The Ground-based Midcourse Defense system was considered operational in 2004 by the Pentagon. Monday's test marked the first test using a "salvo" intercept with multiple interceptors.