New US Antimissile Defense System Could Defend Guam
CREDIT: U.S. Army
This is not a drill: The missile defenses the U.S. is sending to Guam are getting their first real deployment.
The U.S. military is sending the Terminal High Altitude Area Defense System, or THAAD, to defend Guam, a U.S. territory home to Naval Base Guam and Andersen Air Force Base. The North Koreans haven't shown they would be able to hit Guam with the missiles they currently have, and many experts would say the threat is remote, but the U.S. military takes it seriously just in case.
THAAD is among the latest missile-defense technologies, sometimes called antiballistic missile (ABM) systems, but it hasn't yet been used in combat. However, the system has been tested a dozen times since 2005 (most recently in October).
L. David Montague, principal at LDM Associates, and retired president of the Missile Systems Division at Lockheed Missiles and Space Co., said the system works — though there is always some uncertainty with any new weapon or defense. "It's been tested fairly thoroughly," he said, adding that it hasn't yet been used in a real combat situation.
Others aren't as convinced about the system's abilities. Yousaf Butt, scientist in residence at the Monterey Institute of International Studies in California, said the issue is that the tests weren't always that realistic and it isn't clear what countermeasures an adversary might use — though North Korea likely doesn't have anything terribly sophisticated, experts say. The THAAD system is capable of dealing with missile decoys, though that's largely because it attacks missiles after they re-enter the atmosphere, when trajectories are easier to anticipate.
"It's better than nothing," he said, adding that the system can defend areas such as Guam or an air base. It wouldn't be as effective in defending an entire country like South Korea, he said.
THAAD uses X-Band radar to pick up its targets, and has the advantage of being mobile — the launchers are truck-mounted. The system is designed to shoot down incoming missiles within about 155 miles. That gives it enough range to reach just above the atmosphere, where incoming missiles start their descent.
The system is being deployed in conjunction with the Aegis missile system, a ship-based defense, and existing Patriot missile batteries that are designed to shoot down shorter-range missiles (those with ranges in the low hundreds of miles).
In that sense, THAAD differs from the land-based antiballistic missile defenses in the U.S., which are geared to stopping intercontinental ballistic missiles, or ICBMs, from hitting the U.S. mainland. North Korea doesn't have a rocket capable of flying that far.