The two countries set the stage for closer military ties through a 2023 Reciprocal Access Agreement – allowing troop deployments to each other’s territory – Japan’s first defence pact since its 1960 US alliance. Tokyo has since signed similar agreements with the United Kingdom and the Philippines.

On Friday, the two nations will sign a pact on evacuating each other’s citizens during third-country conflicts, Japanese Foreign Minister Takeshi Iwaya told reporters after a meeting with the Australian foreign and defence ministers in Tokyo.

“We shared our recognition of the increasingly tense strategic environment in the Indo-Pacific region and confirmed that we will further strengthen security co-operation between Japan and Australia, and trilaterally among Japan, the US, and Australia,” Iwaya said.

“In particular, we agreed to further strengthen our joint deterrent capabilities.”

The US has been the primary formal treaty ally of both nations for decades, with Japan and Australia key spokes in a regional alliance system with America at its hub.

The firming ties now between Canberra and Tokyo is emblematic of an emerging realisation that Trump’s indifference to the post-World War II, US-led order leaves them without a reliable central co-ordinator, both in Europe and Asia.

“We do face very difficult, challenging strategic circumstances, and as we face them we know our strategic alignment and our strategic trust have never been stronger or deeper,” Australia’s Foreign Minister Penny Wong said after the meeting.

“Australia and Japan face similar challenges. We know Australia and Japan share common interests, and we know now more than ever that we look to each other.”

Trump has demanded Japan and South Korea pay more to maintain US troops in their countries and some officials have called into question the so-called Aukus pact, which is meant to ensure Australia can procure new nuclear-powered submarines from the US.

Last week, US President Donald Trump and Australian Prime Minister Anthony Albanese talked by phone, discussing shared security interests and co-operation on trade and critical minerals.

Australia plans to lift defence spending to 2.4% of GDP by 2034, while Japan targets 2% by 2027. Currently Australia spends about 1.9% of GDP, compared with about 1.4% in Japan, according to data compiled by the Stockholm International Peace Research Institute.

The US is also no longer the unchallenged hegemon of the region, with China’s Navy exceeding it in size and Beijing rapidly arming with planes, missiles and other weapons.

China’s President Xi Jinping showcased his country’s military might last week with a parade of its latest hardware, while earlier this year, his Navy rattled Canberra with unexpected live-fire drills off Australia’s eastern coast.

Still, the US remains central to both Australia and Japan, highlighted by a July logistics pact among their three navies that could turn the hub-and-spoke model into a more balanced triangle. It also has far more money and weapons, including nuclear deterrence.

Even before Australian crews sail on Japanese-built ships, the two militaries have stepped up co-operation, with Ambassador Suzuki touting nearly 40 joint drills in the past year.

Japan also joined a large-scale exercise in Australia with the US and 18 other nations in July, plus drills in the South China Sea that drew Chinese criticism.

There has been “a mutual upgrading of the sense of risk and of threat in the Asia Pacific arising from China’s obvious rise as a strategic power and as a foreign policy actor,” according to Sam Roggeveen, director of the international security programme at Australia’s Lowy Institute.

However, “the threats that China and Russia pose to Japan, are simply not the same threats that they pose to Australia, because Australia is so much further away”.

He added that “geographical distance places limits on the depth of the strategic partnership because neither side will judge the threat to be as acute as the other will”.

Economic ties

The upward trend in relations contrasts with a decade ago, when Japan lost an Australia submarine contract to France – only for Canberra to later scrap the deal in favour of the Aukus deal.

It was seen as a double blow to Japan: a missed chance to open its defence industry and a setback to then–Prime Minister Shinzo Abe’s push for closer ties.

Since then, ties have rebounded on the back of strong trade and bilateral business links.

Japanese companies are the third-largest investors in Australia, with record flows of 2.5 trillion yen last year, and nearly matching levels so far this year.

Japan has been a key trading partner since a 1957 commercial treaty, reinforced by a 2015 free-trade deal and joint membership in major regional pacts.

It was pivotal in developing Australia’s iron ore and liquefied natural gas industries, with Australia still its primary source of energy and a major supplier for commodities such as rare earths.

“The commitments that we’ve made to each other, particularly in our trade agreements, but also in our near alliance-like defence arrangements, are absolutely ironclad commitments,” said Jan Adams, the head of the Australian Department of Foreign Affairs and Trade.

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