According to legend, Robin Hood could split an arrow planted in a target ring. Now imagine a contest where the green guy had to see, then split, an arrow fired in his general direction.
The U.S. Missile Defense Agency’s Ground-based Midcourse Defense system, GMD, has done just that. On Tuesday, using a kill vehicle launched atop a three-stage rocket from Vandenberg Air Force Base in California, the GMD team destroyed a target launched eastward from Kwajalein Atoll in the Pacific, 4,800 miles away, in a test said to approximate an incoming, hostile ICBM. The head-on impact generated a cloud of debris over the Pacific and a loud sigh of relief from GMD contractors and their client. Said MDA director Vice Admiral James Syring at a briefing for reporters, “It actually replicated—without getting into classified details—an operational scenario that we’re concerned about … In this case it was a Pacific scenario.”
Although the GMD was touted as operational 13 years ago, the sponsoring agency has taken a good deal of criticism from agency overseers and arms-control wonks about the cost ($40 billion to date) and a shortage of proof that the interceptor fleet can ever block a madman’s nuclear-tipped ICBM attack.
Until the most recent test, the program’s score stood about even between interception failures and successes, and none of the previous flight tests had matched an interceptor against a fast-moving, distant target representative of an enemy ICBM. The May 30 test did so, we are told, and its success has restored faith among many politicians that the program is not only workable but should grow in scale, perhaps to include a farm of missile silos along the East Coast.
The idea of knocking down ICBMs is an old one, dating to the mid-1960s. A monument to the first concrete effort stands (aptly) outside Concrete, North Dakota: a mammoth phased-array radar station that was to guide the Safeguard anti-ballistic missile system. First declared operational in September 1975, Congress scrapped Safeguard just five months later. Hopes for a more advanced anti-missile missile revived under the Reagan Administration. Called the Strategic Defense Initiative, aka “Star Wars,” it was to stop an all-out superpower attack. That winked out with the collapse of the Soviet bloc.
Growing concerned about a smaller and less sophisticated attack from North Korea or Iran, the Clinton Administration commissioned studies for a scaled-down anti-ICBM plan, but rollout had to wait for the next president. George W. Bush ordered a wide array of missile defenses to get underway and in 2004, the nation heard that the Ground-Based Midcourse Defense system stood ready to defend the homeland.
That required a leap of faith, then and now. While it’s true that dozens of GMD interceptors (meaning, five-foot long “kill vehicles” mounted atop three-stage boosters) can be launched quickly from silos in Alaska and California—44 will be in place by year’s end—installation came so fast that much of that equipment is obsolete. While the MDA and contractors claim that the GMD system is more ready than ever, they also say upgraded hardware and more flight tests are needed.
Is there time for several additional years of work on GMD? Probably. Despite high-flying rhetoric and a parade of ICBM-like missile transporters, North Korea hasn’t yet graduated to the ICBM class. Its longest-range missile test has fallen far short of ICBM range (a minimum of 3,400 miles), and its nukes likely need to shrink in size.
Was the May 30 hit-to-kill success impressive? It was. Unlike Safeguard, GMD interceptors carry no nuclear weapon, or indeed any explosives, capable of reaching out to knock down enemy warheads at a distance. GMD relies on kill vehicles with enough guidance information, and enough agility, to separate from boosters then crash into each and every incoming warhead.
A big question is whether the system can catch all of the enemy missiles, or just a percentage. MDA sounds fully confident that any North-Korea-scale attack is manageable, but arms-control skeptics are dubious, saying even an improved GMD will just motivate an adversary to keep increasing the size of its ICBM booster fleet, in hopes of swamping our defense. And other countermeasures are available, including multiple-warhead “MIRV” missiles, sophisticated decoys, and weapon delivery by non-ICBM methods. Perhaps future tests will help settle the controversy: the next flight test is to see if a volley of GMD interceptors can work well together.