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Pillar II should urgently prioritise the development and deployment of sea- and air-based autonomous systems (Getty Images)
The trilateral security partnership has the potential to deliver meaningful operational advantages within this decade.
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Beyond submarines: Why AUKUS Pillar II matters nowBeyond submarines: Why AUKUS Pillar II matters now
While submarines dominate the headlines, it is Pillar II of AUKUS – the push for cutting-edge capabilities – that could define the partnership’s true legacy.
Since its launch in 2021, the Australia–United Kingdom–United States (AUKUS) partnership has been dominated by discussion of Pillar I – the effort to provide Australia with nuclear-powered, conventionally armed submarines. I addressed the enduring strategic importance of this endeavour in my July 2025 article for The Interpreter. Yet, while the submarine program rightly commands attention for its long-term impact on deterrence in the Indo-Pacific, far less focus has been devoted to Pillar II – the trilateral effort to develop advanced capabilities and emerging technologies such as autonomy, artificial intelligence (AI), and quantum.
The contrast between Pillar I and Pillar II could not be sharper.
If pursued with discipline and focus, Pillar II could prove just as consequential as Pillar I. It has the potential to reshape the regional strategic balance, strengthen US alliances, and accelerate defence-technology innovation across the partnership. But to realise this promise, Pillar II cooperation must be directed towards concrete, high-payoff technologies that can deliver operational advantage in the near, medium, and long term. In the immediate future, the priority should be sea- and air-based autonomous systems. These capabilities can provide usable military advantages in any potential Indo-Pacific conflict while also laying the groundwork for future work.
China continues to expand and modernise its military capabilities at a rapid pace. As the Pentagon’s 2024 China Military Power Report notes, the People’s Liberation Army (PLA) “has sought to modernise its capabilities and improve its proficiencies across all warfare domains to become a joint force capable of the full range of land, air, and maritime as well as nuclear, space, counterspace, electronic warfare, and cyberspace operations.” Faced with the steady rise of Chinese power, the United States’ global commitments, and mounting fiscal pressures at home, it is increasingly clear that US capabilities alone will not be sufficient to deter Beijing. Deepened cooperation with allies and partners will therefore be essential if Washington is to meet its strategic objectives in the region.
Given the Indo-Pacific’s geography, any major conflict with China will likely be dominated by air- and sea-based systems. Recent conflicts in Ukraine and the Middle East illustrate that autonomous systems are rapidly becoming central to modern warfare. Ukraine’s use of sea-based drones, for example, has crippled Russia’s Black Sea Fleet and reopened maritime lanes for Ukrainian shipping. Likewise, Operation Spider Web, carried out by Ukrainian intelligence, demonstrated how long-range drones can penetrate Russian defences and destroy strategic bombers deep inside its territory. In short, the growing role of autonomy, AI, and other emerging technologies signals that the character of warfare is undergoing a profound transformation.
A US Army drone operator controls an Anduril Ghost-X helicopter surveillance drone during military exercises in February 2025 (Sean Gallup/Getty Images)
Beijing clearly recognises this reality. As the 2025 US Intelligence Community Annual Threat Assessment warned, “China is using an aggressive, whole-of-government approach, combined with state direction of the private sector, to become a global S&T [science and technology] superpower, surpass the United States, promote self-reliance, and achieve further economic, political, and military gain.”
In this context, Pillar II of AUKUS – focused on advanced capabilities and emerging technologies – offers a critical opportunity for Australia, the United Kingdom, and the United States to pool resources, accelerate innovation, and compete effectively with China in areas such as autonomy and AI. Yet progress to date has been halting. Work on Pillar II has lagged far behind Pillar I, suffered from a lack of focus, and has not produced any tangible capabilities. As Abraham Denmark and Charles Edel of the Center for Strategic and International Studies observed, “A key lesson of the first years of AUKUS Pillar II is that it is too broad and unfocused.” I fully agree.
Imagine hundreds of low-cost autonomous surface vessels patrolling chokepoints in the South China Sea, or swarms of AI-enabled drones complicating any attempt to blockade Taiwan.
The contrast between Pillar I and Pillar II could not be sharper. Pillar I, the submarine program, is indispensable for long-term deterrence, but its true impact will not be felt until well into the 2030s and beyond. Pillar II, by contrast, has the potential to deliver meaningful operational advantages within this decade – precisely when the risk of conflict in the Indo-Pacific may be greatest. For AUKUS to matter in the decisive years ahead, Pillar II cannot remain a secondary priority.
Given the strategic challenges in the Indo-Pacific, Pillar II should urgently prioritise the development and deployment of sea- and air-based autonomous systems. These platforms would not only provide critical near- and medium-term capabilities, but also play a decisive role in countering a potential Chinese assault or blockade of Taiwan.
Imagine hundreds of low-cost autonomous surface vessels patrolling chokepoints in the South China Sea, or swarms of AI-enabled drones complicating any attempt to blockade Taiwan. These are not distant possibilities – they are the kinds of capabilities Pillar II could deliver within years if properly focused.
The good news is that Australia, the United Kingdom, and the United States each has a vibrant private sector already developing advanced air- and sea-based autonomous systems. In the United States, companies such as Anduril and Mach Industries are designing both air and maritime platforms, while Blue Water Autonomy is developing a full-sized autonomous warship capable of sustained operations in the open ocean at long range.
The United Kingdom also has innovative programs underway. Oceanus 12 XLR, for example, is building an unmanned surface vessel with an endurance of up to 7,500 nautical miles and the ability to operate autonomously for as long as 60 days. Australia, too, is advancing cutting-edge capabilities. Ocius Technology has developed the Bluebottle unmanned surface vessel, powered by wind, solar, and renewable energy – an innovation that could dramatically expand persistent maritime surveillance. In addition, Anduril is partnering with the Australian Department of Defence to develop the Ghost Shark family of autonomous undersea systems.
This brief survey demonstrates that the three AUKUS nations already possess significant industrial expertise in autonomy. What is missing is a coherent government framework to integrate these capabilities across the alliance. If properly harnessed, such collaboration could greatly improve the effectiveness of coalition operations in the Indo-Pacific.
To make this vision a reality, the AUKUS partners should take several concrete steps:
Several other allies and partners – including Japan, South Korea, Canada, and New Zealand – have also expressed interest in joining Pillar II at the appropriate time. Each brings unique scientific and technological strengths that could enhance deterrence in the Indo-Pacific. Once Pillar II is placed on a solid foundation, the AUKUS partners should give serious consideration to expanding participation and inviting these nations to contribute.
AUKUS will not be judged by press releases or long-term procurement schedules, but by whether it delivers capabilities that matter in the years ahead. Pillar I – the submarine program – is essential for the 2030s and beyond. But this decade, when the risk of conflict in the Indo-Pacific is most acute, Pillar II will be the decisive test. If the partners fail to focus and deliver, AUKUS risks being remembered as an ambitious but sluggish industrial project.
If they succeed, Pillar II could transform the strategic balance in Asia, proving that the world’s leading democracies can innovate together at speed, deter aggression, and shape the future of warfare. In short, the true legacy of AUKUS will be written not under the seas, but in the rapid deployment of advanced technologies that can keep the Indo-Pacific free and open.
About the author
Frank A. Rose
Frank A.
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