Again, missile defense has failed the test.

Last week, an interceptor missile failed to launch during a planned test of a proposed ballistic missile shield that has become a major element in President Bush’s defense strategies.

It was the first test in two years. It flopped. Miserably.

Due to an “unknown anomaly,” the antimissile missile wouldn’t turn on. Its mission was to meet a mock warhead fired from Alaska and destroy it in space over the Pacific Ocean. The mock missile was left unmolested.

The United States is spending more than $10 billion a year on a defense system that does not work, has not worked and might never work during a time when the threat from ballistic missiles is overwhelmed by the threat of non-state terrorists and by large budget deficits that undermine economic security. Estimates suggest that between $80 billion and $130 billion has been spent so far on missile defense.

Consistently, tests of the system have failed. The technology to hit a missile with a missile is in its infancy. There have been eight tests of the technology. In five of them, the antimissile missile has managed to hit its target, but only by cheating. The radar signature of the target was enhanced, no decoys were deployed and the time, date and location of the launch were known in advance. Even with those advantages, the system has failed in other tests.

The real kicker is several of these defensive missiles have already been deployed in Alaska. The Pentagon says they’re operational. But it’s clear they won’t work.

Given the shortages of troops and armor in Iraq, and the more realistic threat that a terrorist could smuggle in a chemical, biological or nuclear weapon in an uninspected cargo, can’t we find a better way to spend $10 billion than on the boondoggle of missile defense?