Tokyo Report | Security | East Asia

Japan’s Middle Power Arms Strategy in the Indo-Pacific

Tokyo’s defense exports are becoming tools for building a new middle power security network across the Indo-Pacific.

An illustration showing the upgraded Mogami-class frigate called New FFM (left) next to the current model of the Mogami-class.

Japan’s recent flurry of defense diplomacy – from Manila to Jakarta, Canberra to Wellington – has prompted familiar anxieties about the country’s pacifist commitments. Critics warn of a slippery slope toward remilitarization. Yet this framing fundamentally misreads what Tokyo is actually doing. Viewed clearly, Japan’s defense equipment transfers represent something more modest in military terms, and more significant in strategic ones: the deliberate construction of a middle power cooperation network anchored by shared weapons supply chains.

The scale of Japan’s defense buildup, while notable by its own postwar standards, remains far below what would qualify as militarization by any comparative measure. European middle powers such as France, Germany, and the United Kingdom have long maintained arms export industries and military capabilities that dwarf Japan’s emerging posture. The April 2026 Cabinet decision to remove the long-standing “five categories” restriction on lethal weapons exports is consequential domestically – but it does not make Japan a military great power. What it does is open the door to a different kind of strategic contribution: becoming a supplier and partner within a regional defense ecosystem.

Soeya Yoshihide, professor emeritus at Keio University in Tokyo, has articulated this distinction with unusual clarity. Japan’s postwar diplomacy, he argues, has consistently reflected a multilateral, middle power orientation. The current arms export agenda should therefore be understood through that same lens. The real logic is not deterrence through unilateral military buildup, but the creation of shared weapons supply chains across Asian middle powers — building interoperability, mutual dependence, and strategic alignment through common platforms.

This distinction matters enormously for how Japan frames its approach to potential partners. A China-containment narrative may resonate with the Philippines, which is locked in direct confrontation with Beijing over the South China Sea. But it falls flat – or worse, triggers resistance – in Jakarta. Indonesia, much like India, pursues strategic autonomy between Washington and Beijing. Telling Indonesia that Japanese frigates or submarines will help contain China is, frankly, counterproductive.

The more persuasive argument is one of regional supply chain integration: that participating in a shared defense industrial network enhances Indonesia’s own capabilities and autonomy, while strengthening the collective resilience of Indo-Pacific middle powers. Jakarta signed a Defense Cooperation Agreement with Tokyo in May 2026, and Indonesian naval officials have openly acknowledged interest in Japanese frigates and submarines – but on Indonesia’s own terms, not as a junior partner in an anti-China coalition.

The most compelling evidence for this “middle power supply chain” thesis is the emerging story around Japan’s upgraded Mogami-class frigate, known in Japan as 06FFM or “New FFM.” Australia selected the platform as its future general-purpose frigate, with 11 vessels planned and the first three to be built in Japan.

On May 7, New Zealand identified the same frigate – alongside Britain’s Type 31 – as a finalist in its own replacement program. Wellington’s interest is not simply about hardware specifications. It reflects the logic of operating alongside partners using common platforms: shared parts, shared logistics, shared maintenance, shared training, and ultimately shared operational resilience during crises.

If New Zealand selects the New FFM, Japan’s vision of a shared middle power maritime network would begin to take concrete form. Japan would operate 12 Mogami-class and 12 New FFMs.........

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