The Senkaku Islands, which were not included in the territories that Japan renounced under the 1951 San Francisco Peace Treaty, have long been considered Japanese territory, both historically and under international law.

China, however, has repeatedly intruded into Japan’s territorial waters around the islands. To respond to such activities, Japan should consider revising its domestic laws in case of contingencies at sea.

China's coast guard law, which came into force on Feb. 1, has some points that concern both Japan and the United States.