Asia Defense | Security | East Asia

Japan to Send Combat Units to Philippines-US Balikatan Exercises for the First Time

The move represents a historic shift in Japan’s security engagement with Southeast Asia – and Manila specifically.

U.S. Army Soldiers board a U.S. Army UH-60 Black Hawk helicopter during helocast training at Fort Magsaysay, Philippines, April 30, 2025 as part of Exercise Balikatan 25.

Japan will deploy combat-capable units to participate in the upcoming Philippines-U.S. “Balikatan” military exercises, marking the first time since World War II that Japanese combat troops will set foot on Philippine soil. The move represents a historic shift in Japan’s security engagement with Southeast Asia and highlights the rapidly deepening defense ties between Tokyo and Manila amid rising regional tensions. 

Armed Forces of the Philippines (AFP) Chief of Staff General Romeo Brawner Jr. revealed the plan during a symposium held in Manila on March 24. According to Brawner, Japan’s Self-Defense Forces (SDF) are expected to send combat-capable units to the annual Balikatan exercise scheduled to begin on April 20. 

“Eighty-one years later, this is the first time we will have Japanese combat troops again on Philippine soil,” Brawner said. “Before, we were on opposite sides. This time, we find ourselves on the same side.” 

On March 26, a spokesperson for Japan’s Joint Staff confirmed to The Diplomat that units from the Ground, Maritime, and Air Self-Defense Forces will participate in the exercise. Tokyo is expected to release further details about the size of the deployment and the specific training activities in mid-April, the spokesperson added. 

Balikatan – meaning “shoulder to shoulder” in Filipino – is the largest annual joint military exercise conducted by the United States and the Philippines. The drills typically involve a wide range of activities, including maritime security, amphibious operations, humanitarian assistance, and disaster response. This year’s iteration is expected to be among the largest ever conducted. 

Japan’s expanded role in Balikatan follows the start of enforcement in September 2025 of the Japan-Philippines Reciprocal Access Agreement (RAA). The agreement simplifies procedures for the deployment of troops and military equipment between the two countries for joint exercises, training, and disaster response.

Until recently, Japanese participation in exercises in the Philippines had been limited largely to observers or personnel involved in humanitarian assistance and disaster relief training. According to officials, Japanese units in Balikatan 2026 will now participate in training scenarios involving defensive operations while carrying weapons, representing a significant departure from previous roles.

Japanese Ambassador to the Philippines Endo Kazuya suggested at the same forum that the SDF’s involvement could expand further in the future, describing deeper participation as a natural development given the growing security cooperation between the two countries.

The upcoming Balikatan exercises will involve not only the United States and the Philippines but also participation from Japan and Australia, reflecting a broader shift toward multilateral defense cooperation in the Indo-Pacific.

Brawner emphasized that Japan’s participation will significantly expand the scope of the drills.

“With the participation of Japan, this will expand the scope of our defensive operations,” he said. “We are now working not only with the United States and Australia in preparing to defend the Philippine archipelago, but also our common areas.”

He added that the exercises are intended to prepare for a wide range of contingencies, including natural disasters as well as military crises.

The expansion of Balikatan reflects a broader trend toward deeper coordination among U.S. allies and partners in the region. Defense officials from Japan, Australia, the Philippines, and the United States have increasingly emphasized the importance of joint exercises, intelligence sharing, and operational coordination in maintaining regional stability.

The strengthening of security ties between Japan and the Philippines comes amid rising tensions in the South China Sea. China claims most of the strategic waterway under its “nine-dash line,” a claim invalidated by a 2016 international arbitration ruling under the United Nations Convention on the Law of the Sea. 

In recent years, confrontations between Chinese and Philippine vessels have intensified around disputed features such as Second Thomas Shoal. In response, Manila has sought to deepen security cooperation with allies and partners.

Japan shares similar concerns regarding China’s maritime activities. Tokyo faces its own territorial dispute with Beijing over the Senkaku/Diaoyu Islands in the East China Sea, and Japanese officials have expressed growing concern about China’s expanding military presence in the region.

These shared concerns have helped drive the rapid expansion of Japan-Philippines defense ties. Tokyo has become one of Manila’s key security partners, providing patrol vessels, surveillance systems, and other forms of defense assistance. The two countries have also conducted joint maritime patrols with the United States in the South China Sea and nearby waters.

The deployment of Japanese combat-capable units to the Philippines carries both symbolic and strategic significance.

Historically, memories of World War II – including the tragic Battle of Manila in 1945, one of the most devastating urban battles of the Pacific War – once complicated security cooperation between the two countries. Today, however, Tokyo and Manila have developed a close strategic partnership rooted in shared interests in regional stability and freedom of navigation.

For Japan, the move reflects the gradual evolution of its security policy. While the country’s pacifist constitution continues to place constraints on the use of force, Tokyo has steadily expanded the role of the SDF in international security cooperation.

For the Philippines, deeper defense ties with Japan provide an additional layer of deterrence as Manila seeks to strengthen its ability to protect its maritime territory and respond to regional security challenges.

More broadly, the upcoming Balikatan exercises highlight how security cooperation in the Indo-Pacific is becoming increasingly multilateral. As geopolitical tensions persist, military partnerships involving multiple countries are likely to play a growing role in shaping the region’s evolving security architecture.

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Japan will deploy combat-capable units to participate in the upcoming Philippines-U.S. “Balikatan” military exercises, marking the first time since World War II that Japanese combat troops will set foot on Philippine soil. The move represents a historic shift in Japan’s security engagement with Southeast Asia and highlights the rapidly deepening defense ties between Tokyo and Manila amid rising regional tensions. 

Armed Forces of the Philippines (AFP) Chief of Staff General Romeo Brawner Jr. revealed the plan during a symposium held in Manila on March 24. According to Brawner, Japan’s Self-Defense Forces (SDF) are expected to send combat-capable units to the annual Balikatan exercise scheduled to begin on April 20. 

“Eighty-one years later, this is the first time we will have Japanese combat troops again on Philippine soil,” Brawner said. “Before, we were on opposite sides. This time, we find ourselves on the same side.” 

On March 26, a spokesperson for Japan’s Joint Staff confirmed to The Diplomat that units from the Ground, Maritime, and Air Self-Defense Forces will participate in the exercise. Tokyo is expected to release further details about the size of the deployment and the specific training activities in mid-April, the spokesperson added. 

Balikatan – meaning “shoulder to shoulder” in Filipino – is the largest annual joint military exercise conducted by the United States and the Philippines. The drills typically involve a wide range of activities, including maritime security, amphibious operations, humanitarian assistance, and disaster response. This year’s iteration is expected to be among the largest ever conducted. 

Japan’s expanded role in Balikatan follows the start of enforcement in September 2025 of the Japan-Philippines Reciprocal Access Agreement (RAA). The agreement simplifies procedures for the deployment of troops and military equipment between the two countries for joint exercises, training, and disaster response.

Until recently, Japanese participation in exercises in the Philippines had been limited largely to observers or personnel involved in humanitarian assistance and disaster relief training. According to officials, Japanese units in Balikatan 2026 will now participate in training scenarios involving defensive operations while carrying weapons, representing a significant departure from previous roles.

Japanese Ambassador to the Philippines Endo Kazuya suggested at the same forum that the SDF’s involvement could expand further in the future, describing deeper participation as a natural development given the growing security cooperation between the two countries.

The upcoming Balikatan exercises will involve not only the United States and the Philippines but also participation from Japan and Australia, reflecting a broader shift toward multilateral defense cooperation in the Indo-Pacific.

Brawner emphasized that Japan’s participation will significantly expand the scope of the drills.

“With the participation of Japan, this will expand the scope of our defensive operations,” he said. “We are now working not only with the United States and Australia in preparing to defend the Philippine archipelago, but also our common areas.”

He added that the exercises are intended to prepare for a wide range of contingencies, including natural disasters as well as military crises.

The expansion of Balikatan reflects a broader trend toward deeper coordination among U.S. allies and partners in the region. Defense officials from Japan, Australia, the Philippines, and the United States have increasingly emphasized the importance of joint exercises, intelligence sharing, and operational coordination in maintaining regional stability.

The strengthening of security ties between Japan and the Philippines comes amid rising tensions in the South China Sea. China claims most of the strategic waterway under its “nine-dash line,” a claim invalidated by a 2016 international arbitration ruling under the United Nations Convention on the Law of the Sea. 

In recent years, confrontations between Chinese and Philippine vessels have intensified around disputed features such as Second Thomas Shoal. In response, Manila has sought to deepen security cooperation with allies and partners.

Japan shares similar concerns regarding China’s maritime activities. Tokyo faces its own territorial dispute with Beijing over the Senkaku/Diaoyu Islands in the East China Sea, and Japanese officials have expressed growing concern about China’s expanding military presence in the region.

These shared concerns have helped drive the rapid expansion of Japan-Philippines defense ties. Tokyo has become one of Manila’s key security partners, providing patrol vessels, surveillance systems, and other forms of defense assistance. The two countries have also conducted joint maritime patrols with the United States in the South China Sea and nearby waters.

The deployment of Japanese combat-capable units to the Philippines carries both symbolic and strategic significance.

Historically, memories of World War II – including the tragic Battle of Manila in 1945, one of the most devastating urban battles of the Pacific War – once complicated security cooperation between the two countries. Today, however, Tokyo and Manila have developed a close strategic partnership rooted in shared interests in regional stability and freedom of navigation.

For Japan, the move reflects the gradual evolution of its security policy. While the country’s pacifist constitution continues to place constraints on the use of force, Tokyo has steadily expanded the role of the SDF in international security cooperation.

For the Philippines, deeper defense ties with Japan provide an additional layer of deterrence as Manila seeks to strengthen its ability to protect its maritime territory and respond to regional security challenges.

More broadly, the upcoming Balikatan exercises highlight how security cooperation in the Indo-Pacific is becoming increasingly multilateral. As geopolitical tensions persist, military partnerships involving multiple countries are likely to play a growing role in shaping the region’s evolving security architecture.

Takahashi Kosuke is Tokyo Correspondent for The Diplomat.

Japan-Philippine defense cooperation

U.S.-Japan-Philippine security cooperation

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