This week's test was the second of a scheduled three. Last fall an interceptor missile successfully destroyed its target, but almost by accident. It suffered initial navigational mistakes and found the target only after luckily homing in on a nearby decoy balloon. One more test will be held this spring, the last before Mr. Clinton's scheduled decision. Even if it proceeds flawlessly, the White House will not know for sure whether the system will consistently work as intended.
Missile defenses have to be highly reliable to be effective.
Mr. Clinton will need to resist any impulse to approve the missile system as a political tactic to protect Vice President Al Gore from charges that the administration has left the country defenseless against missile attacks from terrorist states. The latest test failure may help him there by weakening support for immediate deployment. Although Republican leaders in Congress are still urging speedy deployment, some Republican senators are now urging that a decision on the system be deferred. The defensive system under consideration is not meant to provide a shield against the substantial missile forces of Russia or even China, but to shoot down the handful of missiles that unpredictable countries like North Korea or Iran might soon be able to launch against the United States. It would still be one of the most complicated weapons systems ever built.