Japan and Australia: Toward a More Autonomous and Resilient Partnership

As Washington’s reliability wavers, Tokyo and Canberra are learning to depend on each other.

Japan’s Defense Minister Nakatani Gen, right, and Australia’s Defense Minister Richard Marles held a joint press announcement aboard the Japan Maritime Self-Defense Force’s Mogami-class stealth frigate JS Mikuma at the Japanese naval base in Yokosuka, Japan, on Sept. 5, 2025.

The security environment in the Indo-Pacific is undergoing a profound transformation. Cooperation among revisionist powers, including China, Russia, and North Korea, is deepening, while the strategic priorities of the United States — the country that has long underpinned the regional order — are also changing. At the same time, technological advances in areas such as artificial intelligence, autonomous systems, unmanned platforms, quantum technologies, and cyber capabilities are fundamentally changing the character of warfare and the sources of military advantage.

Against this backdrop, Japan and Australia have deepened their comprehensive security partnership across military and economic domains. What matters increasingly is their ability to build both strategic autonomy and strategic resilience.

Strategic autonomy does not mean “independence” from the United States. Rather, it means reducing excessive dependence on any single major power and preserving greater room for strategic choice and freedom of action. Strategic resilience, meanwhile, refers to the ability to withstand and recover from strategic shocks, whether they take the form of military conflict, economic coercion, supply-chain disruption, or energy crises. Together, these two concepts provide a useful framework for thinking about the current state and future direction of Japan–Australia cooperation.

For much of the post-Cold War period, both Japan and Australia benefited from what might be called “dual dependence.” In security terms, both relied heavily on the United States, while economically they developed increasingly deep interdependence with China. This arrangement allowed them to enjoy security at relatively low defense costs while benefiting substantially from China’s economic growth.

As U.S.–China rivalry and broader great-power competition intensify, however, this model is becoming increasingly difficult to sustain. Yet neither replacing dependence on the United States with dependence on China, nor pursuing economic decoupling from China, is a viable option for either country. Rather, the goal is to diversify dependence itself — to expand the range of partners and capabilities available so that neither country becomes excessively vulnerable to the decisions of any single major power.

This is the direction the Japan–Australia relationship has taken over the past few years. While maintaining their respective alliances with the United States, Japan and Australia have strengthened their own capabilities and built a more autonomous bilateral security relationship — one that goes beyond simply “supplementing” the U.S. military presence in the region.

The cooperation surrounding the Australian Navy’s acquisition of Japanese-designed Mogami-class frigates is a good example. Its significance extends well beyond the transfer of a particular platform. Developed into sustained cooperation across joint development, production, maintenance, and future technologies, it could strengthen the defense industrial bases of both countries —........

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