Instead, it's time for quiet but pointed talks with China about prospects for political change within North Korea. China, which supplies the North with food, fuel, and trade, as well as political support, is the one country with any real leverage over its behavior. The critical question now is whether, in the wake of the Cheonan episode, Beijing will continue to act as the Kim dynasty's enabler. Chinese officials have condemned the attack but have so far refused to assign the blame to North Korea. Beijing is in a difficult position, however, since it doesn't want to sour relations with the South, a far more significant trading partner. And the Chinese know that Pyongyang's nuclear bluster and spasmodic attacks on the South reinforce America's security alliances in the Far East.
Where the Koreas are concerned, China craves stability above all else. This gives the Obama administration an opening to "heighten the contradictions" in Beijing's policy; namely, that its support for the Kim dynasty ensures chronic instability on the Korea peninsula. Sooner or later, this Cold War anachronism will implode, and Washington and Beijing ought to start preparing jointly for that eventuality. For now, containment offers a better guide to U.S. policymakers than engagement.