China's standoff with Japan over the rocky Senkaku (Diaoyu) Islands has entered its second month. The current confrontation, however, is more dangerous than is commonly believed. China's past behavior in other territorial disputes demonstrates why the Senkaku standoff is primed to explode.

Since 1949, China has been involved in 23 territorial disputes with its neighbors on land and at sea. Seventeen of them have been settled, usually through compromise agreements. Nevertheless,...