Yama Sakura, an annual command post exercise involving U.S., Japanese and Australian troops, kicked off at Camp Itami, Japan, Aug. 25, 2025. (U.S. Army)

Elements of a U.S. Army task force that recently deployed a hypersonic missile system to Australia are participating in a command post exercise in Japan this week, according to a U.S. Army Japan spokesman.

Members of the Hawaii-based 3rd Multi-Domain Task Force are in Japan for the seven-day Yama Sakura exercise, which kicked off Monday, Manuel Torres-Cortes said by text message Monday.

The Army announced last month that the task force had sent the hypersonic missile system to Australia’s Northern Territory for the biennial Talisman Sabre exercise, marking the weapon’s first overseas appearance.

The service didn’t provide information about the task force’s elements in Japan. In Australia, U.S. soldiers briefed allied troops about the Dark Eagle system.

Hypersonic weapons travel at speeds exceeding Mach 5, or five times the speed of sound.

The Army gave no indication that the weapon, with an estimated range of 1,700 miles, was fired in Australia.

Also participating in Yama Sakura are soldiers from U.S. Army Japan, Hawaii’s 25th Infantry Division, Washington State’s I Corps, and troops from Japan and Australia, Torres-Cortes said. The exercise involves 2,500 Japanese, 700 American and 120 Australian troops.

A command post exercise gauges participants’ ability to manage and respond to a simulated crisis. It typically involves commanders, command staff and communications between participating headquarters.

U.S. soldiers brief allied troops about the Dark Eagle hypersonic missile system in Australia’s Northern Territory, July 9, 2025. (Perla Alfaro/U.S. Army)

Yama Sakura opened at Camp Itami, headquarters of Japan’s Middle Army in Hyogo prefecture. The annual training is also taking place at Camp Senzou in Hyogo and Camp Asaka in Tokyo, Torres-Cortes said.

“The global community is facing a crisis due to significant changes to the international order,” Lt. Gen. Makoto Endo, commander of the Japan Ground Self-Defense Force’s Middle Army, told troops gathered to launch the drills. “It is critical for us to work together to improve coordination between our three nations.”

A video of Endo’s remarks, along with those by 25th ID commander Maj. Gen. James Bartholomees and 1st Australian Division deputy commander Brig. Gen. Shane Gabriel was provided by Torres-Cortes after the opening ceremony.

The international community is entering a new era of competition with serious challenges to the rules-based order, Bartholomees said.

“These challenges are being felt acutely in the Indo-Pacific,” he said. “The importance of the Japan-U.S. alliance and trilateral cooperation between Japan, the U.S. and Australia can’t be understated.”

The generals didn’t specify those challenges, but U.S. commanders have identified China as a threat to regional security.

Beijing is rapidly expanding its military capabilities and has vowed to take control of Taiwan — by force, if necessary. China also claims Japan-administered islands in the East China Sea.

Meanwhile, North Korea has deployed troops to assist Russia in Ukraine and continues to advance its nuclear and missile technology.

This year’s exercise marks the third time that Australia has joined Yama Sakura, Gabriel said.

The training is focused on enhancing command and control, targeting and fires, and communication, he said.

Yama Sakura complements the Orient Shield field exercise involving U.S. and Japanese forces in Japan, Sept. 16-24, Torres-Cortes said.