China surely understands this. Therefore one of the most conspicuous events of current diplomacy is Beijing’s support in principle of North Korean denuclearization. At the same time, the prospect of disintegration or chaos in North Korea evokes at least two major concerns in China. The first is the political and social effects of a North Korean internal crisis on China itself, re-enacting events familiar from millennia of Chinese history. The second involves security in Northeast Asia. China’s incentive to help implement denuclearization will be to impose comparable restraints on all of Korea. To be sure, South Korea has no visible nuclear program or announced plans for it, but an international proscription is another matter.

China would also have a stake in the political evolution of North Korea following denuclearization, whether it be a two-state solution or unification, and in restrictions on military deployment placed on North Korea. Heretofore, the administration has urged China to press North Korea as a kind of subcontractor to achieve American objectives. The better—probably only feasible—approach is to merge the two efforts and develop a common position jointly pursued with the other countries involved.