Wall Street Journal Editorial
June 21, 2006

As we went to press in the U.S. last night, morning was breaking at the Musudan-ri launch facility in the remote northeast of North Korea. It's possible we'll wake up to the news that Pyongyang has tested the long-range ballistic missile that is fully fueled and which U.S. satellites have monitored for more than a month.

If so, we hope we'll also learn that the U.S. responded by testing its newly operational missile defense system and blowing the Korean provocation out of the sky. What better way to discourage would-be nuclear proliferators than to demonstrate that the U.S. is able to destroy their missiles before they hit our allies, or the U.S. homeland. Even a miss would be a useful learning experience all around.

Consider what's at stake. We've known for years that North Korea has several nuclear weapons at the very least and is developing the missile technology to threaten America. Pyongyang's test missile is believed to be a Taepodong-2. A two-stage version could reach Alaska, Hawaii or the West Coast, according to a study in March by the Center for Nonproliferation at the Monterey Institute of International Studies, while a three-stage model could reach all of the continental U.S.

North Korea may not yet have the ability to miniaturize a nuclear warhead--but then again it may. In any event, it's small comfort that the Taepodong-2 is probably inaccurate. If it misses Seattle, that's not necessarily good news for Tacoma or Portland.

The last time North Korea launched a missile that caught the world's attention was in August 1998, when it shot a Taepodong-1 over Japan and into the Pacific. Pyongyang has since tested shorter-range missiles many times, including as recently as March. Its inventory of ballistic missiles totals about 800, including 100-200 Nodongs and Taepodong-1s capable of reaching Japan. North Korea is also developing a land-based mobile missile known as the Taepodong-X, with a range of 4,000 kilometers that could land anywhere in Japan.

Missile exports have also long been a major source of foreign exchange for Pyongyang, with customers in Pakistan (whose "Ghauri" missile is a renamed Nodong) and throughout the Middle East. Its longtime best customer is Iran, which last year was reported to have purchased technology that allowed it to extend the range of its Shahab-3 missile to 3,500 kilometers from 1,500. In the blunt words of the German daily Bild last December, "this means that the 'madmen of Iran' could reach targets in the whole of Germany."

All of which demonstrates once again the need for the missile defenses that the Bush Administration has steadily been developing. The objective of the integrated system--which U.S. officials stress is "limited" and still under development--is to provide a "layered" defense, with multiple opportunities to take shots at an incoming missile. The highly complex system depends on swift coordination among elements based on land, at sea, and in the air or space.

On the ground, a key element are the interceptor missiles newly deployed at Fort Greeley, Alaska, and Vandenberg Air Force Base in California. There are also interceptors aboard the Navy's Aegis cruisers, two of which are currently patrolling near North Korea. Sensors are located aboard ships, in space, and at several sophisticated radar stations world-wide.

North Korea clearly intends any launch as an act of intimidation, part of its long-held belief that nuclear threats give it political leverage. Knocking the missile out of the sky, or even trying to, would tell the North that it can't succeed with such tactics. It would also reassure Japan and other U.S. allies that we have the will to protect them from rogue madmen. The demonstration effect would be useful around the world, not least in Iran.

As North Korea weighs a launch, it's a useful moment to recall how we got to this pass: Amid the arms-control era of the Cold War, the U.S. chose to defend itself against attack by plane or ship or ground but not by missile. One reason North Korea--and Iran--decided to invest scarce resources into developing nuclear weapons and ballistic-missiles is simply this: The U.S. was vulnerable.

The emerging missile defense system is making that less true, and a North Korean test launch is an ideal time to demonstrate that we are willing and able to defend ourselves.

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