For all China's stern injunctions to Japan to remember wartime history, its bumbling aggression in Southeast Asia suggests it also could use a refresher course.

The arrival of a Chinese oil rig in waters claimed by both China and Vietnam is a case in point. Demonstrations in Vietnam over China's bullying deteriorated into a series of attacks by Vietnamese on foreign businesses, many run by Taiwanese with Chinese workers, that resulted in two dead and scores injured.

China, of all countries, should know better. In the decades before World War II, it suffered territorial incursions and economic depredations at the hands of Japan. These, in turn, sparked widespread popular protests and economic boycotts.