New threats have emerged. The first is North Korea, which is believed to have as many as 10 nuclear warheads and recently carried out its third nuclear test. The Pyongyang regime, according to House Intelligence Committee Chairman Mike Rogers, R-Mich., has missiles "that can reach U.S. shores."
Missile defense is an attempt to buttress the power to retaliate with the ability to fend off incoming warheads before they arrive. The Defense Department has said it would spend $1 billion to deploy more missile interceptors along the West Coast to shoot down a North Korean missile, increasing the total number from 30 to 44 in the next four years.
It's a reasonable and useful step, at a cost that would seem trivial if the system were ever called on to deflect an attack.
With regard to Iran, the administration took a different step, scrapping the last phase of a missile defense system that has elicited vigorous objections from the government of Russia -- which regarded the program as a threat to neutralize its nuclear weapons. The Pentagon insisted the U.S. decision was based on technical problems, which may be true. But it may also serve to pave the way to better relations and even arms reductions with Moscow.
The danger still exists, of course, but President Obama has made it clear he will take military action if necessary to keep Iran from getting the bomb. If he succeeds in deterring Tehran from that course -- or in forcibly preventing it -- the European missile shield will not be needed quite so soon.
American missile defense still has a lot of hurdles to surmount before it can offer a reliable safeguard against attack. But even an imperfect system is better than nothing. And no one can doubt the need to keep pursuing it.
-- The Chicago Tribune