Missile defense aimed at intercepting only missiles targeting Japan

Japan Policy & Politics, Jan 10, 2005

TOKYO, Jan. 9 Kyodo

Japan has decided to use its missile defense system solely to intercept ballistic missiles targeting Japan, not missiles that pass over Japan and target other countries including the United States, government sources said Saturday.

The government has decided to limit the scope of interception by the missile defense system, to be deployed in fiscal 2007, because intercepting missiles that are targeted at other countries would be construed as collective self-defense.

According to the Japanese government's interpretation, under international law Japan has the right to collective self-defense -- which is the right to use force to counter a foreign attack on an allied country -- but Japan's war-renouncing Constitution forbids the exercise of that right.

The government will explain the decision during Diet deliberations if it submits legislation on missile defense to the upcoming ordinary session, the sources said.

Political analysts say, however, that Japan will likely be hard-pressed by the United States, which is expected to show discontent over the decision as it would bar Japan from taking any action against missiles aimed at the United States that pass over Japanese territory.

The target of a ballistic missile can be predicted by its speed and angle as it leaves the atmosphere.

A missile fired by North Korea, for example, will not pass over Japan if it is targeted at the U.S. mainland, but if it is targeted at Hawaii and Guam it will pass through Japanese skies.

The government had once judged it possible to shoot down missiles that travel over Japan by interpreting such an action as exercising its right to individual self-defense given the possibility that some missile parts could fall on Japanese territory.

But it finally determined that intercepting missiles not targeting Japan would pose a constitutional problem, the sources said.

A gray zone remains, however, as the government had said in past Diet sessions that in cases where the precise destination of a missile cannot be predicted, it will consider the probability of it targeting Japan as high and such a launch as an armed attack against Japan, allowing interception.

Senior officials of Japan's Defense Agency also said interception would be inevitable in cases where Japan cannot specify where the ballistic missile will land.

Japan has recently decided to purchase a missile interception system from the United States, apparently to deal with possible ballistic missile attacks from North Korea.

Under the system, Japan would intercept an incoming ballistic missile outside the atmosphere, using an SM-3 standard missile carried on destroyers equipped with the Aegis air defense system.

If the SM-3 fails to shoot it down, a ground-based PAC-3 missile will try to intercept it before it reaches its target.