Evolution of the Australia-Japan Security Partnership: Toward a Softer Triangle Alliance with the United States?

This paper examines how and why the Australia-Japan defense and security partnership has evolved, what policy implications this new partnership has for the U.S.-Japan alliance system, and what constraints the further advancement of trilateral security cooperation faces.
The U.S. strategic position and defense posture has catalyzed the evolution of the Australia-Japan security and defense partnership. This partnership has helped to sustain the U.S.-Japan alliance through, for instance, deepening Japan's involvement in defense and security arenas, as was seen in the protection of JSDFs in Iraq by Australian forces.
Still, the Australia-Japan security and defense partnership, a relatively new element in the bilateral relationship, is not based on an alliance system like Japan and the United States. It is still in a formative stage and thus requires strong shared strategic interests and common regional understandings to develop.
The convergent views and interests, especially over the approach to the rise of China as a military power, are helping the further development of the trilateral cooperation with the United States within a rapidly changing regional environment.
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Evolution of the Australia-Japan Security Partnership: Toward a Softer Triangle Alliance with the United States?
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