Or has it? Let's say, for the sake of argument, that North Korea really did test a working nuclear weapon yesterday (as opposed to a smaller, cruder device, which may be just as plausible). How big a disaster would that really be? For years, intelligence estimates have said that North Korea already had the material for several nuclear bombs. Most analysts believed that it was only a matter of time before Kim went nuclear. Compared to India's nuclear test in 1998, which really did take the U.S. by surprise, North Korea's announcement was practically a foregone conclusion.
The real news is that it's not all bad. Now that Pyongyang has confirmed what everyone suspected, it may find it has a less leverage to play the U.S. off against the other parties in the dispute. Everything about China's response to the North Korean test suggests that the Chinese are furious with Kim. The same appears to be true of South Korea, which until now had been pushing to make nice with the North. In in the wake of the test, it's almost impossible to see how Kim can avoid action by the U.N. Security Council. And though truly punitive sanctions are unlikely, at least at first, the prospect of the international community finally condemning Kim in a single voice has to count as some kind of progress.
The two main risks posed by a nuclear North Korea, of course, are very real proliferation and black-market sales in nuclear technology. But both dangers may be exaggerated. Kim has already said he won't peddle his wares beyond his borders, a claim that may be more credible than it sounds. It's safe to assume that terrorist groups wouldn't hesitate to use a nuclear device against an American city if they ever got their hands on one; but that heightens the risk to the supplier too. Any evidence that a nuclear terror bomb had been supplied by Pyongyang would result in that country's liquidation. Proliferation is harder to stop, though it's doubtful that there's much public appetite in countries like Japan and South Korea for an expensive, destabilizing arms race. One of the first things the U.S. should do now is reassure those nations that the U.S. is committed to their defense and they are protected by America's nuclear umbrella. Far from what North Korea hopes, the U.S. will probably feel compelled to become more assertive in the region, not less.
But firmness doesn't have to lead to confrontation. The only realistic option for containing North Korea is the same as what it was before the test. It's easy for nuclear wannabes to decry the hypocrisy of the great powers and proclaim their right to join the nuclear club; but once they get there, they have to play by the club's rules. Kim Jong Il may have believed that getting the bomb was the best way to defend himself against the threat of regime change; but should he ever use his new weapon, regime change administered in the form of massive nuclear retaliation by the U.S. and its allies is now assured. And that points to the last unintended benefit of North Korea's nuclear test. After more than a decade of drift, indecision and disagreement, the world may finally have stumbled upon a coherent policy toward North Korea. It's called deterrence. At least we know it's worked before.