U.S., Japanese and Australian forces opened Yama Sakura 91 at Camp Asaka, Japan, on Sept. 3, conducting a trilateral command post exercise focused on readiness and interoperability in the Indo-Pacific.
The exercise is the latest iteration of the long-running Yama Sakura series, which has been conducted annually for decades as a cornerstone of the U.S.-Japan military alliance. The inclusion of Australia reflects the deepening trilateral security relationship among three of the Indo-Pacific’s most capable militaries.
The command post exercise tests the ability of the three nations’ military headquarters to plan and coordinate operations together, a capability that would be critical in any contingency involving China’s expanding military activities in the Western Pacific.
The timing of the exercise coincides with a Quad Sherpas meeting in New Delhi on Sept. 3, where senior officials from the United States, India, Japan and Australia met to prepare for a higher-level engagement. Together, the military exercise and diplomatic meeting signal continued strengthening of the multilateral architecture designed to counter Chinese influence in the region.
For American security interests, interoperability with Japan and Australia is foundational to the U.S. defense posture in the Indo-Pacific. Japan hosts approximately 54,000 U.S. military personnel, and Australia’s northern bases are increasingly integrated into American force planning.
China has rapidly expanded its military capabilities in recent years, including the world’s largest navy by number of vessels, advanced missile forces and growing power-projection capacity. The trilateral exercises are designed to ensure that the U.S., Japan and Australia can operate as a combined force if deterrence fails.
U.S. Indo-Pacific Command, the Japanese Ministry of Defense and the Australian Defence Force are jointly managing the exercise.