Marc Jacob Prosser
The 2023 Yama Sakura exercise, the largest yet, marked a new era in trilateral military cooperation. More than 6,000 personnel from the Australian Defence Force, the Japan Self-Defense Forces (JSDF) and the United States military participated in the large-scale exercise, called Yama Sakura 85, in December.
The inclusion of the Australian military signifies the evolving dynamics in the Indo-Pacific. Since its launch in 1982, Yama Sakura had been conducted bilaterally between the Japan Ground Self-Defense Force (JGSDF) and the U.S. military.
Its expansion “shows the deepening bonds between the three nations to the world, which would reinforce response capabilities and deterrence in East Asia,” said Lt. Gen. Ryoji Takemoto, commanding general of the JGSDF’s Ground Component Command. He emphasized the exercise’s strategic significance and how it enhances trilateral operational capabilities.
Takemoto also stressed interoperability among the forces, urging participants to reflect on other exercises such as Talisman Sabre and Orient Shield to improve capabilities. His focus on workflow, systems, equipment, and command and control emphasized the importance of harmonizing different military doctrines and practices.
In the face of threats such as the Chinese Communist Party’s increasingly assertive maritime activities and North Korea’s ballistic missile launches, Yama Sakura highlights the critical role of allied cooperation in maintaining a Free and Open Indo-Pacific.
Retired JGSDF Maj. Gen. Nozomu Yoshitomi noted the exercise’s evolution since his initial participation in Yama Sakura 9.
“Back then, a large-scale invasion by the [former] Soviet Army was the exercise scenario. These days, the backdrop of the exercise is China’s assertive behavior in the region. It underscores how the effective cooperation between [J]SDF and the U.S. military is getting more critical in Yama Sakura and the real world,” Yoshitomi, a professor at Nihon University’s College of Risk Management, told FORUM.
The exercise’s image as a remnant of the Cold War “has recently changed as it has started to rigorously invite outside participants and focus on multidomain operations beyond a pure bilateral ground-warfare setting,” according to Hirohito Ogi, a senior research fellow at the Asia Pacific Initiative and the Institute of Geoeconomics at the International House of Japan, a Tokyo-based think tank. “This shift highlights the importance of integrating allied forces and capabilities across different force components to enhance the effectiveness of our limited resources,” Ogi told FORUM.
Yama Sakura 85 also highlighted strengthening defense ties between Australia and Japan, which have deepened their security partnership in recognition of the need for a united response to regional challenges.
“After being observers of this excellent exercise for 10 years, we are very proud to have been invited to be full participants in this iteration,” said Maj. Gen. Scott Winter, commanding general of the Australian Army’s 1st Division.
The militaries conducted Yama Sakura drills across Japan and at U.S. Joint Base Lewis-McChord in Washington state. The exercise focused on theoretical scenarios, testing, and developing joint air, land and sea operational strategies. Enhanced complexity and multidomain and cross-domain operations were introduced to reflect the evolving nature of warfare.
Yama Sakura 85 is part of a series of command post drills leading to larger field exercises. It demonstrates the commitment of Australia, Japan and the U.S. to a secure and stable Indo-Pacific, sending a clear message of unity and preparedness to potential adversaries.
Marc Jacob Prosser is a FORUM correspondent reporting from Tokyo.