By David King
They are the Japanese army’s newest fighting force – a crack group of highly trained marines whose sole purpose is to storm one of the country’s 10,000 islands and repel any invader.
For the next three weeks, they’re going to call Australia home as they prepare to land on a remote Queensland beach with US and local forces in a simulation of what they could face in a potential conflict.
Major General Toshikatsu Musha, commander of Japan’s amphibious rapid deployment brigade at Camp Ainoura in Sasebo, Japan.Credit: David King
The amphibious rapid deployment brigade (ARDB) was created just seven years ago as tensions mounted between Japan and China over disputed islands in the East China Sea. Since then, the brigade has grown from one regiment to three – 3000 troops in total.
This masthead was given exclusive access to the brigade’s base at Camp Ainoura, at Sasebo on the southern Japanese island of Kyushu, before the mission to Australia for Talisman Sabre, the massive international military exercise about to get under way in Sydney on Sunday.
Japan’s contingent of 1500 military personnel is its largest deployment to the exercise so far and will include 450 Japanese marines as well as two navy destroyers, a tank landing ship and amphibious vehicles.
Commanding officer major general Toshikatsu Musha said the chance to test his troops with Australian and US forces was extremely valuable, and he was looking forward to more challenging conditions than the calm waters around their training base.
“The higher the waves we have, the better training we can have. So it’s very beneficial to us,” he said.
“Another benefit is we can work with the US Marine Corp and the Australian soldiers, so we can strengthen our mutual understanding and also strengthen interoperability.”
Talisman Sabre involves 30,000 personnel from 19 countries, plus three observer nations, with war games stretching from Jervis Bay in NSW to the Northern Territory and for the first time this year, Papua New Guinea. Giant warships have already started to arrive in Australia’s northern waters.
It is also the largest combined training activity between the Australian Defence Force and the United States military, which the ADF says reflects “the closeness of our alliance”.
Japan, Australia and the US are quickly stepping up their military co-operation in a strategic push against China and the exercises will be the first step in delivering a commitment from the countries’ defence ministers to work together on amphibious warfare.
Camp Ainoura in Sasebo, pictured in June this year, the base of Japan’s amphibious rapid deployment brigade.Credit: David King
Simulated beach landings near Rockhampton will involve the 31st US Marines as well as the Japanese units amid concerns in all three countries about China’s military build-up and deepening ties between North Korea and Russia.
China has sent spy ships to monitor the Talisman Sabre exercise regularly since 2017 with a keen interest in how the Japanese navy works with US and Australian forces. Defence Minister Richard Marles said he fully expects China to monitor the operation again in 2025.
Tomohiko Satake, an associate professor at Aoyama Gakuin University in Tokyo and a Japan-Australia security expert, said Australia, the US and Japan have moved from training for abstract scenarios to planning for the actual prospect of conflict.
“It’s stepped up to the more high-end co-operation between two militaries, so apparently they’re preparing for the war scenarios, actual contingencies, such as Taiwan Strait, or the Korean Peninsula,” he said.
He argues the broad purpose of the co-operation between the three nations is collective defence or deterrence against any use of force by China to change the regional status quo.
He says the Japanese marines are primarily for defence of Senkaku Islands, uninhabited but strategically useful islands near Taiwan that China also claims and calls the Daioyu Islands.
Members of Japan’s amphibious rapid deployment brigade training at Camp Ainoura, in Sasebo, Japan, in June 2025.Credit: David King
Taking the plunge
Although they’re colloquially known as Japanese marines, the ARDB mission is different from their counterparts in the US Marine Corp who are considered an expeditionary force, immediately deployable for combat in a foreign nation. The Japanese marines’ focus is on island defence.
Training in the near-tropical climate of Camp Ainoura involves all aspects of capturing and holding an island. Live-fire exercises are common on the base and swimming and rescue drills are on high rotation, alongside leaping from heights equivalent to the deck of a ship.
Sergeant Tsubasa Sagae and Sergeant Kentaro Yamanaka will take part in the Australian exercise.Credit: David King
Sergeant Kentaro Yamanaka was already serving in the army when the ARDB recruiters came knocking. He put his hand up immediately. “They go to the front, it’s a very aggressive unit, so I joined,” he said. He and counterpart Sergeant Tsubasa Sagae are excited at the prospect of training in Australia.
“I’d like to compete with another nation,” Sagae says. “I have to focus on accuracy and how quickly I can fire the mortar. It’s my mission.”
David King travelled to Japan on a Foreign Press Center Japan fellowship.
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