On July 4, Beijing announced it had launched a new sea patrol to replace a group of ships that, in June, were an integral part of China’s effort to control waters far from its shoreline. In an extraordinary move last month, Beijing claimed part of the Pacific Ocean as sovereign Chinese water. On June 6, China’s Ministry of Transport launched “a special maritime law enforcement operation in the waters east of Taiwan Island.” Vessels from the Fujian and Guangdong Maritime Safety Administrations, the East China Sea Navigation Support Center and the East China Sea Rescue Bureau took part, sailing eastward...