As President Barack Obama wound up his visit to Japan last month, the Japanese and American governments released a joint statement outlining the outcome of his talks with Prime Minister Shinzo Abe. Almost every newspaper article I saw focused on the same few issues — above all, the two leaders’ failure to reach an agreement on the Trans-Pacific Partnership, a 12-nation trade agreement. There was one exception: The Okinawan daily Ryukyu Shimpo ran on its front page the large headline, “U.S. Military Presence in Okinawa to Be Permanent.”

Ryukyu Shimpo had picked up on a sentence in the joint statement that other papers had ignored: “The early relocation of Futenma Marine Corps Air Station to Camp Schwab and consolidation of bases in Okinawa will ensure a long-term sustainable presence for U.S. forces.” Okinawans have been fighting for decades to have the Marines’ air operations removed from the entire Ryukyu archipelago. In January, residents of Nago on Okinawa Island, where Camp Schwab is located, overwhelmingly re-elected a mayor who has vowed to block the plan to resettle Futenma there, rejecting a pro-relocation candidate strongly supported by Mr. Abe’s party.

Okinawans are among the most downtrodden people in the region. In premodern times, the small Ryukyu Kingdom, as it was known then, was a tributary state of China and Japan simultaneously. Japan treated residents badly after fully annexing the islands in the 1870s. The Battle of Okinawa at the end of World War II killed one in four inhabitants. In the postwar period the United States turned the Ryukyu Islands into a military colony.

Even since the islands reverted to Japan in 1972, they have been exploited for military purposes as a result of agreements between the Japanese and American governments. The strategic importance of Okinawa Prefecture to the two governments has increased recently owing to its proximity to the Senkaku/Diaoyu Islands, to which both Japan and China lay claim.