In the latter half of this month, security cooperation among allies and like-minded countries in the Indo-Pacific further advanced. The Quad Foreign Ministers’ Meeting and the Japan-U.S., Japan-ROK, and Japan-Philippines summit meetings confirmed closer coordination and cooperation to promote regional security and stability. Multilateral security cooperation also deepened through joint naval activities involving the United States, Australia, and Canada, as well as Japan’s dispatch of instructors to an Australia-hosted Indo-Pacific coast guard workshop.

Meanwhile, China deployed over 100 naval vessels in the East China Sea, Yellow Sea, and western Pacific, conducted repeated “joint combat patrols” around Taiwan, and carried out aircraft carrier flight operations in the western Pacific. In the South China Sea, a Dutch naval vessel, expected to participate in RIMPAC 2026, confronted the Chinese navy. China’s maritime expansion and gray-zone activities also continued, including incursions around the Senkaku Islands, confrontations between Chinese and Taiwanese authorities’ vessels near the Pratas Islands, Chinese maritime militia activities near the Philippines, and the discovery of Chinese underwater surveillance devices in Indonesia. Reports further indicated that China’s maritime activities were expanding beyond the Indo-Pacific, including fishing fleet operations off Argentina.