North Korea’s recent ballistic-missile test has triggered new demands in the United States that China pressure Pyongyang to cease its disruptive and provocative behavior. Senate minority leader Charles Schumer is the latest voice to join the chorus. Such calls have taken place for many years with few signs of success. There is growing anger and frustration in U.S. political and policy circles with Beijing’s tepid support for economic sanctions and other coercive measures against its longtime ally.
The underlying assumption is that China has tremendous influence over North Korea and is the one country that could bring Pyongyang to heel. New York Times columnist Tom Friedman once stated that Beijing could end North Korea’s misconduct “tomorrow” with one uncompromising message to that country’s government.

There is no doubt that China has more influence over North Korea than any other country. And the potential for even greater leverage exists. China provides a majority of North Korea’s food and energy supplies, so a cutoff—or even a major reduction—in those supplies would likely create a crisis for Pyongyang.