MAKE THE NIGHTMARE REALITY:

The United States has given Chinese leaders no incentive to incur the risk of having the North Korean state unravel, which could lead to both a refugee crisis and the prospect of a united Korea allied militarily with the United States.

For Beijing to take such a gamble, either there would have to be a large potential reward for action or an equally large potential downside for inaction. Current U.S. policy includes neither feature, and that has to change. If Washington is not willing to offer Beijing the one "carrot" that might cause Chinese leaders to dump the country's troublesome client--ending the U.S. alliance with Seoul upon Korean reunification--the Obama administration must boost China's anxiety level.

The most effective way to do that is to invoke the specter that South Korea and Japan might decide to build their own nuclear arsenals if North Korea continues its menacing ways, especially its quest for nuclear weapons. Chinese officials would not be happy about a South Korean nuclear arsenal, and the last thing in the world they want to see is a nuclear-armed Japan.

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