In September 2021, Australia, the United States and the United Kingdom announced the establishment of AUKUS, a trilateral security partnership that marked one of the most significant strategic shifts in Australian foreign policy since the end of the Cold War. Australia cancelled its A$90 billion conventional submarine contract with France and instead committed to developing a nuclear-powered submarine fleet with American and British support.
At the time, the strategic rationale appeared straightforward. China’s military capabilities were expanding rapidly, US–China competition was intensifying, and the Indo-Pacific was increasingly viewed as the centre of future geopolitical rivalry. By integrating more deeply into the US-led security architecture, Australia hoped to strengthen its military capabilities, gain access to advanced technologies, and signal its long-term strategic alignment with its allies.
Five years later, AUKUS remains in place. The world, however, is no longer the same as it was in 2021.
From New Submarines to Second-Hand Submarines
AUKUS consists of two pillars. Pillar I focuses on helping Australia acquire nuclear-powered submarines, while Pillar II promotes cooperation in advanced defence technologies such as artificial intelligence, quantum technologies, cyber security, autonomous systems, electronic warfare, hypersonic weapons, and underwater drones.
Initially, Australia expected to receive at least one newly built Virginia-class submarine from the United States, supplemented by second-hand vessels before transitioning to the future SSN-AUKUS fleet. By 2026, however, the plan had shifted. Australia agreed to acquire three second-hand Virginia-class submarines rather than any newly built vessels.
The Australian government argues that this approach will reduce costs, simplify maintenance and training requirements, and accelerate the development of an operational nuclear submarine capability. Critics, however, see the change as evidence that Australia is accepting a less ambitious option than originally promised.
More importantly, the controversy highlights a deeper structural issue: Australia is investing hundreds of billions of dollars into future defence capabilities while remaining heavily dependent on the United States for submarine production, maintenance, key technologies, and delivery schedules.
What Exactly Is AUKUS?
AUKUS is frequently described as an “Asian NATO”, but this comparison is misleading.
Unlike NATO, AUKUS is not a formal military alliance. Traditional military alliances are typically based on legally binding treaties that commit members to defend one another in the event of an attack. NATO’s Article 5 is the most prominent example. AUKUS contains no such provision.
When AUKUS was announced, Australian Prime Minister Scott Morrison described it as an “enhanced trilateral security partnership”. British Prime Minister Boris Johnson referred to it as a “new trilateral defence partnership”, while US President Joe Biden called it “a new phase” in trilateral security cooperation. None of them used the language of a military alliance.
In practical terms, AUKUS offers Australia military capability development rather than a security guarantee. Australia gains access to submarines, advanced technologies, intelligence sharing and industrial integration, but not an explicit promise that the United States would automatically come to its defence.
This distinction matters. Australia is not purchasing an insurance policy. It is making a long-term strategic investment built upon several assumptions: that the United States will remain the dominant power in the Indo-Pacific, that America can produce enough submarines, that China will remain Australia’s primary strategic challenge, and that large nuclear-powered submarines will continue to be central to future warfare.
The World Is No Longer the Same
The strategic environment has changed considerably since 2021.
Australia’s relationship with China has partially stabilised after years of trade tensions. China remains a major strategic concern, but bilateral relations are no longer as hostile as they were during the Morrison era.
At the same time, Donald Trump’s return to the White House has reintroduced a more transactional approach to alliances. From pressuring NATO members to increase defence spending to demanding greater burden-sharing from partners, American foreign policy increasingly reflects an “America First” logic.
Even AUKUS itself has come under scrutiny within Washington. Some voices in the Pentagon have questioned why the United States should transfer submarines to Australia when America already faces its own submarine shortages.
This raises an uncomfortable question: has Australia built a forty-year defence strategy around a partner whose policies can change dramatically with each election cycle?
If submarines are built in the United States, maintained through American systems, upgraded with American software, and armed with American weapons, how much operational independence does Australia actually possess?
Lessons from Ukraine and the Middle East
Another major shift concerns the nature of warfare itself.
AUKUS was conceived largely through the lens of traditional naval power. Submarines, fleets, maritime control and great-power competition were central assumptions.
However, the wars in Ukraine and the Middle East have transformed perceptions of future conflict. Low-cost drones, AI-enabled targeting systems, satellite intelligence and electronic warfare have repeatedly demonstrated the ability to destroy far more expensive military assets.
Increasingly, military analysts argue that future wars may be defined not by large fleet battles but by autonomous systems, distributed operations and rapid technological innovation.
This raises another important question: is Australia investing too heavily in a single platform?
A nuclear-powered submarine remains a valuable military asset. Yet future military superiority may depend more on AI, cyber capabilities, quantum technologies and autonomous systems than on any individual weapons platform.
Australia’s Real Challenge: Understanding China
Ultimately, AUKUS is built upon a fundamental assumption that China represents Australia’s most significant long-term security challenge.
But what exactly is China?
Supporters of the “China threat” narrative point to Beijing’s expanding military capabilities, increased pressure on Taiwan, growing influence in the South China Sea and broader efforts to reshape regional power balances.
Chinese leaders, however, argue that their priorities are national unity, regime stability and economic development rather than territorial expansion. From Beijing’s perspective, military modernisation is intended to prevent external interference and preserve domestic stability.
Whether China is a revisionist power seeking to overturn the international order or a rising power primarily concerned with its own security remains a subject of intense debate.
For Australia, this question is crucial. If policymakers misunderstand the nature of the challenge they face, no amount of military spending will necessarily produce better security outcomes.
An AUKUS 2.0?
The debate today is no longer whether Australia should abandon AUKUS. The more relevant question is what kind of AUKUS is appropriate for the world of 2026.
Five years ago, AUKUS was presented as the answer to China’s rise. Today, some of the greatest uncertainties stem not from China but from the United States, from changing technologies, and from evolving forms of conflict.
Australia may therefore need to rebalance AUKUS itself. Greater emphasis on Pillar II—AI, quantum technologies, cyber security, autonomous systems and domestic industrial capability—could prove more valuable than an overwhelming focus on submarines alone.
Five years ago, AUKUS answered the questions of 2021. The challenge now is whether it can answer the questions of 2026 and beyond.