Okinawa residents may be starting to wonder what the future holds in Japan's new security landscape and whether their prefecture, with its heavy U.S. military presence, will be the front line of defense against China.

As Japan is set to debate whether to lift its self-imposed ban using collective self-defense and how to handle "gray zone" incidents that stop short of full-fledged military attacks, Okinawa's importance as a strategic hub is coming into focus.

When U.S. President Barack Obama said after the summit in Tokyo with Prime Minister Shinzo Abe that the Senkaku Islands in the East China Sea are covered by the bilateral security treaty, which obliges the United States to defend Japan if they are attacked, apparently reassured Abe and Okinawa Gov. Hirokazu Nakaima.