From a public relations perspective, China's moving its most advanced oil rig into South China Sea waters disputed by Vietnam for exploratory drilling on May 2 was a disaster. It sparked clashes between rival flotillas of boats that in turn led to protests in Vietnam in which Chinese people were killed and factories looted and burned. Tensions are likely to ease now that the platform has been towed back north a month ahead of schedule. Why it has been shifted is unclear, but what is certain is that where territorial disputes are concerned, negotiations are always preferable to unilateral actions.

A series of actions in the South and East China seas in the past year have battered China's international image. From the declaration last November of air traffic restrictions over contested maritime claims that overlapped zones put in place by Japan and South Korea, to islands disputed with Vietnam and the Philippines, to the placement of the oil rig, China has been in the unusual position of being both assertive and defensive. Overseas pressure has forced Beijing to explain its actions. Regional concerns have been heightened about China's military build-up and intentions.

The defensive posture has not always been handled well. Beijing took a month before making its case for the legality of the rig's presence. Vietnam said it was within its 200 nautical mile exclusive economic zone; China explained it in terms of history. The rig's removal was variously said to have been because its work had been completed ahead of schedule and as a precaution against typhoons. It may also have been an effort to head off a threat by Vietnam's prime minister, Nguyen Tan Dung, to file a legal challenge to the territorial claims under international law, as the Philippines has done.