Japan, explained.
Royal Australian Air Force aircraft fly in formation with Japan Air Self-Defense Force jets (Japan Self-Defense Force/Defence Images)
Shared threats and defence priorities make a formal trilateral framework a logical next step.
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Australia, Japan and New Zealand should double down on collaborationAustralia, Japan and New Zealand should double down on collaboration
China’s assertiveness and a more uncertain US strategic posture make the case for Australia, Japan and New Zealand to double down on one another. Canberra and Tokyo already have a strong partnership. The next step is to treat a more security-conscious Wellington not as an adjunct, but as part of a durable trilateral framework.
Prime Minister Sanae Takaichi’s resounding election victory on 8 February was a clear endorsement of her reform agenda and vision for Japan’s place in the Indo-Pacific. Her domestic hand has been strengthened by Beijing’s more bellicose behaviour in recent months. Takaichi and her defence minister, Shinjirō Koizumi, have rallied Japan’s allies, while efforts to bolster the nation’s Self-Defense Forces (JSDF)continue apace.
Canberra is an increasingly important partner to Tokyo. In December 2025, the Labor government strongly criticised Beijing when a Chinese military aircraft locked its radar on Japanese fighter jets near Okinawa. That same month, Defence Minister Richard Marles stated Australia would continue its work with Japan to uphold the rules-based international order.
Almost a year earlier, an unannounced Chinese naval flotilla had transited through the Tasman Sea, undertaking live fire drills, prompting the New Zealand defence minister to remark that more investment was needed in the region in response to China’s power projection.
The three nations share the vision of a Free and Open Indo-Pacific, a concept developed by Japan’s former prime minister Shinzo Abe, stressing international law, freedom of navigation, and quality infrastructure development. That vision runs counter to unilateral attempts by China to alter the regional status quo.
To uphold the vision, Canberra, Tokyo and Wellington see sustained US military power in the region as critical, particularly in the South China Sea, to check China’s expansionism. Washington’s 2026 National Defense Strategy commits to maintaining that posture.
The Australia–Japan partnership is even more important as the two accelerate defence and diplomatic coordination.
Takaichi, Albanese and Luxon have all made overtures to the White House. Takaichi and Koizumi, in particular, have developed a strong rapport with their American counterparts. Japan, as a major power, will contribute more to this arrangement. Australia, while one step removed from the potential trouble spot of Taiwan, is a proactive participant. New Zealand is becoming more active as well.
Yet a distracted United States creates strategic uncertainty. The Australia–Japan partnership is therefore even more important as the two accelerate defence and diplomatic coordination. It also sharpens the logic of tighter New Zealand–Australia planning within a wider trilateral framework.
To adjust to this new age of great-power politics, Tokyo is rapidly increasing its military spending, which is projected to hit 2% of GDP two years ahead of schedule. This represents AU$80 billion of spending in 2026, with more than $9 billion allocated to stand-off missiles, greatly improving Japan’s long-range strike capabilities. Tokyo’s large-scale procurement of drones will also help it adapt to the new technological realities of warfare. Wellington, too, will lift defence spending towards 2% of GDP and acquire new platforms such as MH-60R Seahawk helicopters, interoperable with Australia and Japan.
In addition, Koizumi is overseeing changes to export policies around combat equipment, signalling Japan will remove existing restrictions to improve the capabilities of like-minded nations. This “top-level sales diplomacy” is key to creating a more favourable security environment for Japan.
It will also allow Australia to build on its procurement of 11 Mogami-class frigates from Japan for the Royal Australian Navy in a AU$10 billion deal. These vessels can travel up to 10,000 nautical miles without refuelling and offer greater firepower with smaller crews. New Zealand, declaring it seeks to act as a “force multiplier with Australia”, is also interested in Mogami-class frigates to replace its Anzac-class boats.
This collaboration is both a template and a foundation for wider efforts to secure a Free and Open Indo-Pacific. Making up half the Quad, Tokyo and Canberra are signalling a front-footed approach to Washington and New Delhi. Japan is also increasingly engaged with AUKUS Pillar II, which involves advanced defence-tech cooperation. Meanwhile, New Zealand has promising tech start-ups that could contribute to Pillar II.
Trilateral exercises continued last year in a show of strength and interoperability. In July, the largest-ever iteration of Exercise Talisman Sabre in Australia brought together more than 30,000 personnel, including New Zealand among the 19 participating nations, and featured amphibious operations and live-fire of surface-to-ship missiles. September’s Exercise Bushido Guardian, hosted by Japan at Misawa Air Base, emphasised “fifth-generation integration”, which centred on F-35 fighter jets. More than 700 personnel from the three nations’ air forces participated.
Separately, Wellington and Tokyo thickened ties in December 2025 by signing intelligence-exchange and logistics-support agreements.
While President Trump has sharp words even for his allies, his administration understands the challenge that China poses to America’s preeminent regional position. Secretary of State Marco Rubio is a long-time China hawk, while Under Secretary of Defence for Policy, Elbridge Colby, has written lucidly on the importance of alliances in blunting China’s rise.
Australia and Japan are therefore well placed to support a favourable balance of power, while New Zealand bolsters legitimacy and South Pacific presence. As Canberra and Tokyo deepen bilateral ties both diplomatically and militarily, Wellington’s defence reinvestment should be treated as mutually reinforcing, creating a more resilient Indo-Pacific posture.
About the author
Reuben Steff
Dr.
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