Japan Deploys Combat Troops to Philippines for First Time Since WWII
Tokyo's 7,000-strong trilateral exercise with US and Philippine forces signals shift from pacifism to proactive deterrence, reshaping regional security architecture as China weaponizes rare-earth supply chains.
Japan has positioned over 7,000 troops across expanded trilateral exercises with US and Philippine forces, deploying 420 Ground Self-Defense Force personnel to Salaknib 2026—the first Japanese combat forces on Philippine soil since World War II. The deployment, which opened on 6 April and runs through late May 2026, marks Tokyo’s most assertive regional security posture in decades, backed by a record ¥9.04 trillion ($58 billion) defense budget approved for fiscal 2026.
From Constitutional Pacifism to Proactive Deterrence
The Salaknib exercises represent the operational manifestation of Japan’s decade-long security pivot. What began as incremental constitutional reinterpretation has crystallized into forward-deployed combat capability. The Diplomat notes that deployment follows the September 2025 enforcement of the Japan-Philippines Reciprocal Access Agreement, which streamlines procedures for troop movements, joint exercises, and equipment transfers between the two nations.
“Eighty-one years later, this is the first time we will have Japanese combat troops again on Philippine soil.”
— General Romeo Brawner Jr., Armed Forces of the Philippines Chief of Staff
The scale of Japan’s commitment extends beyond Salaknib. Concurrent participation in the larger Balikatan 2026 drills, running from 20 April through late May, involves ground forces, naval assets, and coordinated operations in the South China Sea. February 2026 saw Japan, the US, and the Philippines conduct their first trilateral naval exercises in the Luzon Strait and Bashi Channel—waters directly adjacent to Taiwan and critical to Beijing’s maritime access.
Defense Industrial Buildup and Strike Capability
Tokyo’s operational tempo is underwritten by unprecedented fiscal commitment. The ¥9.04 trillion budget approved in December 2025 represents a 9.4% increase from the previous year, pushing Japan to the NATO-standard 2% of GDP defense spending threshold by March 2026. PBS NewsHour reports the budget funds deployment of Type-12 surface-to-ship missiles with 1,000-kilometer range to Kumamoto by the end of fiscal 2026, extending Japan’s anti-ship strike envelope across much of the East China Sea.
Defense Minister Shinjiro Koizumi framed the budget as a response to what he termed Japan’s most severe postwar security environment. The allocation includes ¥160 billion ($1 billion) for next-generation fighter development with the UK and Italy, targeting 2035 deployment. Naval News notes the budget also accelerates Tomahawk cruise missile integration and naval vessel construction, transforming the Japan Maritime Self-Defense Force from primarily defensive to expeditionary-capable.
Supply Chain Decoupling and Rare-Earth Weaponization
China’s response has extended beyond diplomatic protest to economic coercion. In January 2026, Beijing halted rare-earth and rare-earth magnet exports to Japanese firms, according to the Foundation for Defense of Democracies, directly targeting defense Supply Chains dependent on materials critical for missile guidance systems, radar components, and electric motor magnets.
| Year | China Dependency | Countermeasure |
|---|---|---|
| 2010 | 90% | Baseline (pre-diversification) |
| 2025 | ~60% | Alternative sourcing, stockpiling |
| 2026 | Target: <50% | Deep-sea mining, North American partnerships |
Japan has accelerated countermeasures. In January 2026, Tokyo began deep-sea mining tests near Minamitori Island at 6,000-meter depth, targeting rare-earth deposits estimated to supply domestic needs for centuries. The Center for Strategic and International Studies notes Japan has also formalized technology transfer agreements with the US on rare-earth processing, signed in October 2025, and is partnering with North American rare-earth producers to build processing capacity outside Chinese control.
CEPA analysis shows Japan reduced Chinese rare-earth dependence from 90% in 2010 to approximately 60% by 2025 through strategic stockpiling, alternative sourcing from Australia and Vietnam, and domestic recycling programs. The current export ban is accelerating this trajectory, with Japan targeting sub-50% dependency by 2027.
Quad-Adjacent Architecture and Regional Implications
The exercises signal evolution of what analysts term a “Quad-adjacent” minilateral framework. While no formal trilateral alliance exists, overlapping bilateral defense agreements—the US-Japan alliance, the US-Philippines Mutual Defense Treaty, and the new Japan-Philippines security partnership—create operational redundancy that functions similarly to collective defense.
Japan’s deployment occurs as China intensifies gray-zone operations in the South China Sea. The Philippine Information Agency confirmed Australia is also participating in Salaknib 2026, adding a fourth node to what is effectively Quad operational coordination without formal alliance structure. This approach allows participants to maintain strategic ambiguity about automatic mutual defense obligations while building interoperability for contingencies ranging from humanitarian response to high-intensity conflict.
Radio Free Asia quoted regional analyst Shen noting that Japan’s ground force participation “indicates a rising possibility of joint US-Japan-Philippines responses to South China Sea conflicts,” while acknowledging that overlapping partnerships are beginning to resemble a more connected network despite the absence of formal trilateral treaty obligations.
The exercises also have direct implications for Taiwan contingency planning. February’s trilateral naval drills in the Luzon Strait positioned forces in waters that would be critical in any Taiwan Strait scenario, demonstrating both interoperability and political will to operate in contested zones. Beijing views this coordination as encirclement and has responded with increased military exercises near Taiwan and the Philippines’ exclusive economic zone.
What to Watch
Defense budget execution through fiscal 2026 will test whether Japan can sustain 9.4% annual growth amid demographic headwinds and debt-to-GDP ratios exceeding 250%. Type-12 missile deployment timelines and Tomahawk integration schedules are concrete metrics of strike capability maturation.
Rare-earth supply chain diversification progress matters beyond defense. Japan’s semiconductor industry, already reshoring production through TSMC partnerships and government subsidies, depends on rare-earth inputs for wafer fabrication equipment and chip packaging. Success in deep-sea mining and North American processing partnerships could provide blueprint for broader industrial decoupling.
The frequency and scope of trilateral exercises will signal whether this represents temporary deterrence posturing or permanent security architecture. If Salaknib becomes annual with expanding ground force participation, it formalizes Japan’s role as regional military actor rather than US auxiliary. Conversely, any reduction in tempo following resolution of immediate Taiwan tensions would suggest tactical rather than strategic reorientation.
Beijing’s response spectrum extends from economic coercion to military escalation. Watch for Chinese pressure on ASEAN states participating in or hosting exercises, semiconductor export controls targeting Japanese firms, and People’s Liberation Army exercises that mirror trilateral drill scenarios. The January rare-earth export halt established precedent for weaponizing supply chains—extension to other critical materials or technologies would force broader decoupling decisions across Japanese industry.