A new Korean war: Five scenarios

With tensions high, American spy satellites are looking for evidence that the North Koreans are getting ready to test another nuclear weapon — just as they did in 2006 and 2009 — or shoot off some more long-range missiles. It is a sure way to grab headlines and rattle the neighborhood. In the past, such tests have ratcheted up tension, and could do so again. But they are not the Obama administration’s biggest worry. As one of Mr. Obama’s top aides said months ago, there is reason to hope that the North will shoot off “a nuclear test every week,” since they are thought to have enough fuel for only eight to twelve.

Far more worrisome would be a decision by Pyongyang to export its nuclear technology and a failure by Americans to notice.

For years, American intelligence agencies missed evidence that the North was building a reactor in the Syrian desert, near the Iraq border. The Israelis found it, and wiped it out in an air attack in 2007. Now, the search is on to find out if other countries are buying up North Korean technology or, worse yet, bomb fuel. (There are worries about Myanmar.)

In short, the biggest worry is that North Korea could decide that teaching others how to build nuclear weapons would be the fastest, stealthiest way to defy a new American president who has declared that stopping proliferation is Job No. 1.