By Xu Yongzhi

According to reports, the Japan Ground Self-Defense Force (JGSDF) has recently dispatched troops to participate in the US-Philippines Balikatan and Salaknib exercises, with a relatively large deployment. Analysts believe that this marks the first time since WWII that Japan has sent formed combat units to land on the Philippine territory, signaling a major upgrade in bilateral security ties between Japan and the Philippines. The international community should remain highly vigilant against Japan's relevant moves and the growing military collusion between Japan and the Philippines.

In recent years, defense cooperation between Japan and the Philippines has shown increasingly systematic and institutionalized characteristics. The signing of relevant agreements has laid the groundwork for the normalized and institutionalized cross-border deployment of the Japan Self-Defense Force (JSDF). In 2024, Japan and the Philippines signed the Reciprocal Access Agreement (RAA), which came into effect in 2025, removing legal obstacles to joint exercises between the two sides. In January this year, the two sides also signed the Acquisition and Cross-Servicing Agreement (ACSA), enabling their forces to provide each other with supplies such as fuel and ammunition, as well as services including equipment maintenance and the use of bases and facilities during training and other activities. At present, the two sides are also negotiating a General Security of Military Information Agreement (GSOMIA). Some analysts note that once the agreement takes effect, Japan and the Philippines will be able to share relevant intelligence in real time.

Meanwhile, Japan's military assistance and arms sales to the Philippines have shown an accelerated expansion. As early as 2016, the two sides signed the Agreement concerning the Transfer of Defense Equipment and Technology. Since then, Japan has begun providing military assistance and conducting arms sales to the Philippines. In 2017, Japan provided the Philippines with second-hand patrol aircraft. In 2023, Japan established the Official Security Assistance framework, aimed at providing defense equipment to other countries. The Philippines became one of the first recipients, receiving military assistance worth 3.1 billion yen over three years. In March this year, five coastal surveillance radar systems provided by Japan to the Philippines were deployed successively, aimed at enhancing the Philippines' situational awareness of surrounding waters. The Philippines is also the first recipient of Japan's complete sets of defense equipment exports. In 2020, the two sides signed an arms sales contract worth about 100 million US dollars. Under the contract, Japan sold three FPS-3 radars and one TPS-P14 mobile radar to the Philippines, marking Japan's first major deal in the export of finished defense equipment. At present, the two sides are also in talks on the export to the Philippines of command and control systems, decommissioned frigates, and Type 03 surface-to-air missile systems. Among these, the export of command and control systems is closely related to real-time intelligence sharing in bilateral and multilateral settings.

Japan's troop deployment to the Philippines comes against the backdrop of strengthened military collusion among Japan, the US, Australia and the Philippines. The four parties held a defense ministers' meeting in 2025, stating that they would take joint measures to enhance deterrence and rapid response capabilities. This year, in addition to Japan, Australia will also participate in the land-based components of the US-Philippines Balikatan and Salaknib exercises. Previously, joint exercises among the four parties were mainly conducted at sea. As US allies, the simultaneous participation of Japan and Australia in land-based exercises in the Philippines signals the four parties' intent to realize joint deterrence.

The intensive upgrading of military cooperation among Japan, the US, Australia and the Philippines is by no means a simple matter of regional defense coordination. In essence, it reflects attempts by certain outside countries and countries not directly concerned to turn the Philippines into a forward operating outpost and jointly pursue so-called first island chain denial. Behind such an escalation of military cooperation lies a strong sense of targeting and provocation. Relevant countries should recognize that forming blocs and building exclusive military small cliques will not only intensify camp confrontation and severely destabilize the regional security landscape, but also backfire on their own national interests, ultimately harming themselves.

(The author is from the China Institute of Contemporary International Relations）