Updated 7:02 p.m. EST
The Defense Department on Tuesday improved a spotty record by destroying a mock intercontinental ballistic missile over the Pacific with a new hit-to-kill vehicle meant to protect the homeland against the growing threat from North Korea.
The launch of a Ground-based Midcourse Defense, or GMD, interceptor missile launched from Vandenberg Air Force Base in California against an ICBM-class target fired from the Reagan Test Site on Kwajalein Atoll in the Marshall Islands resulted in a "direct collision," the Pentagon's Missile Defense Agency said in a statement.
"The intercept of a complex, threat-representative ICBM target is an incredible accomplishment for the GMD system and a critical milestone for this program," Vice Adm. Jim Syring, the agency's director, said in a statement. "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."
Advocates of the system -- which had failed in eight of 17 previous tests -- said the success on Tuesday validated the investments in the program.
"This was a good day for homeland defense and a bad day for Kim Jong-un," said Thomas Karako, a senior fellow for the Missile Defense Project at the Center for Strategic and International Studies, a think tank in Washington, D.C., referring to the North Korean dictator.
The test that MDA estimated at $244 million had long been planned for May 30 but came as North Korea was stepping up its own medium and short-range missile tests and boasting of developing an ICBM with the range to hit the U.S. mainland with a "miniaturized" nuclear warhead that could survive reentry from space.
For the U.S., the intercept marked the first live-fire test against an ICBM-class target for the GMD missile, which is being developed by Boeing Co., according to the Missile Defense Agency.
The test was also the first for the new CE-II Block 1 kill vehicle, which uses newly-designed divert thrusters to correct previous problems with the guidance of the kill vehicle, according to the Union of Concerned Scientists, a nonprofit in Washington, D.C. that opposes nuclear arms proliferation. Divert thrusters are the small motors that make course adjustments when the kill vehicle is homing on its target and can make the difference between a hit and a miss, it said.
Karako of CSIS described it as "the latest configuration of the previous CE-II vehicle."
The hit-to-kill missile was designed to strike and destroy an incoming long-range missile by kinetic force, often compared to hitting a bullet with a bullet.
In previous tests, intercept team leaders knew the general trajectory of the target beforehand.
Chris Johnson, a spokesman for MDA, would not confirm that the trajectory of the target in the Tuesday test was given to the intercept team, but said that Vandenberg had a "general launch window."
Overall, the MDA said in a fact sheet, "Testing to date has given us confidence in the basic design, effectiveness, and operational capability for short, medium, and long-range ballistic missile defense."
Since the integrated defense system was initiated in 2001, MDA said that "75 of 92 hit-to-kill intercept attempts have been successful across all programs." The programs included GMD, the Aegis Ballistic Missile Defense (BMD), Terminal High Altitude Area Defense (THAAD), and PATRIOT Advanced Capability-3.
Nine of 17 GMD tests before May 30 were successful intercepts, MDA said. Of the eight that failed, three were because the interceptor and the booster failed to separate. Another failure was attributed to a kill vehicle guidance error in the final seconds of flight.
Other reasons for failures were cited as kill vehicle's infrared sensor cooling malfunctioned; interceptor failed to launch due to problematic software configuration; interceptor failed to launch after a silo support arm did not retract, triggering an automatic abort; and, simply, kill vehicle and system sensor performance issues.
During the test Tuesday, multiple sensors provided target acquisition and tracking data to the Command, Control, Battle Management and Communication (C2BMC) system. The Sea-Based X-band radar, positioned in the Pacific Ocean, also acquired and tracked the target, MDA said, and the GMD system received the target tracking data and developed a fire control solution to intercept the target.
In recent weeks, President Donald Trump has repeatedly warned of the threat from North Korea developing missiles capable of hitting the U.S. mainland with a nuclear warhead and has pressed China to rein in Kim Jong-un.
North Korea has detonated underground nuclear devices three times in the last five years and has greatly accelerated its testing of ballistic missiles. In its 12th test launch this year, North Korea on Monday fired a missile that flew about 280 miles before landing in the Sea of Japan.
The U.S. has also been concerned about North Korea switching from liquid to solid fuel for its missiles, which would significantly cut the time for launch preparations and limit the time for detection by satellite.
North Korea's actions appeared to have altered the policy initiatives of new South Korean President Moon Jae-in, who had spoken during the campaign of the need for new negotiations with North Korea rather than confrontation and also questioned the placement of the U.S. Terminal High Altitude Area Defense (THAAD) system in South Korea.
In phone talks Tuesday with Japanese Prime Minister Shinzo Abe, Moon said he would press for more sanctions on North Korea before considering new talks, South Korea's Yonhap news agency reported.
"I agree with the prime minister's (Abe's) words that now is not time for dialogue with North Korea, but a time to heighten sanctions and pressure," spokesman Park Soo-hyun quoted Moon as saying.
-- Brendan McGarry contributed to this report.
-- Richard Sisk can be reached at firstname.lastname@example.org.