Duterte's visit clearly revealed Japan's strategic calculations

Japan's media have made no secret of their disappointment in Philippine President Rodrigo Duterte moving closer to China. Japan has been trying to draw Southeast Asian nations - the Philippines included - to its side to put pressure on, if not confront, China.

The Asahi Shimbun said the Japanese and the US governments have been enhancing their relations with the Philippines as part of their efforts to counter China's "aggressive maritime expansion".

The Mainichi Shimbun called close cooperation between Japan, the United States and the Philippines the "core" of Japan's security policy in the South China Sea.