Japan Doubles Down on Maritime Security Cooperation |
Asia Defense | Security | East Asia
Japan Doubles Down on Maritime Security Cooperation
A recent visit highlights Tokyo’s seriousness.
Japanese Defense Minister Koizumi Shinjiro (left) meets with Indonesian Defense Minister Sjafrie Sjamsoeddin after signing a new defense agreement in Jakarta, Indonesia, May 4, 2026. (X/Koizumi Shinjiro)
Japanese Defense Minister Koizumi Shinjiro visited Indonesia and the Philippines from May 3 to 6 to meet separately with Indonesian Minister of Defense Sjafrie Sjamsoeddin and Philippine Secretary of National Defense Gilberto Teodoro. The main takeaway from these visits is that Japan has bolstered its security cooperation with Indonesia and the Philippines in an effort to enhance maritime security in East Asia.
Koizumi and Sjafrie signed the Defense Cooperation Arrangement (DCA), expanding cooperation in the areas of people-to-people exchanges, education and research, joint training, maritime security, humanitarian assistance and disaster relief (HA/DR), as well as defense equipment and technology cooperation. Under this arrangement, the two countries agreed to launch the “Integrated Defense Dialogue Mechanism” in order to further expand and deepen their defense partnership through dialogue at the ministerial level, vice-ministerial level, and between senior military leaders. The ministers also agreed to advance discussions on the protection of military information, with a view to strengthening operational cooperation between the two militaries. They also agreed to hold working-level consultations to advance cooperation in the field of defense equipment and technology that would contribute to enhancing maritime deterrence capabilities.
Meanwhile, in the Philippines, Koizumi and Teodoro reaffirmed their strong opposition to any unilateral attempts to change the status quo by force or coercion in the East China Sea and the South China Sea, and expressed serious concerns over China’s coercive activities there. Additionally, they confirmed their intention to ensure the integrated functioning of existing and new consultation platforms at the levels of ministers of defense, vice ministers, and working-level officials of both defense establishments, covering policy, operations, and defense equipment and technology cooperation. The two ministers also agreed to establish an institutional framework for information sharing to enhance maritime domain awareness capabilities. They also issued a joint statement on defense equipment and technology transfer. In it, the ministers stated that, with the transfer of Abukuma-class destroyers to the Philippines in mind, they would establish a working group to discuss education and training, maintenance support, operational cooperation and information sharing, and appropriate management after transfer.
Given the content of the agreements between Japan and Indonesia and the Philippines, we can identify three major priorities Japan aims to achieve in maritime security cooperation with each country. The first is Japan’s emphasis on practical, effective security cooperation with the two countries to maintain maritime security in East Asia. By promoting integrated........