In a few weeks time, senior U.S. and Chinese leaders will sit down in Washington for their annual "strategic dialogue." Given rising tensions in the South China Sea, that dialogue is taking on increasing importance.

In 2001, when an American EP-3 spy aircraft operating over the South China Sea collided with a Chinese air force interceptor jet near Hainan Island, Chinese and U.S. leaders managed to defuse the situation and avoid a military confrontation. Today, such an incident in the South China Sea, where China and several Southeast Asian countries have competing territorial claims, would almost certainly lead to an armed clash — one that could quickly escalate into open war.

Last month, at the annual Shangri-La Dialogue security conference, Singaporean Prime Minister Lee Hsien Loong conveyed the deep apprehension of the countries of the Association of Southeast Asian Nations about the potential for an armed conflict between China and the United States. The good news is that U.S. and Chinese representatives took the conference as an opportunity to signal subtly their willingness to ease tensions and continue to engage with each other.