AUKUS, Australian SSN Program and Their Implications

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2021-09-21 | James Bosbotinis

The announcement on 15 September 2021 of the Australia, United Kingdom, and the United States (AUKUS) trilateral security partnership marks a significant development in the Indo-Pacific regional architecture, constituting the latest example of a minilateral grouping deriving from the US alliance system. Whilst the acquisition, under the auspices of AUKUS, of nuclear-powered attack submarines (SSNs) will provide a major qualitative capability upgrade for Australia, and the Royal Australian Navy (RAN). In this respect, and more broadly, the development of the AUKUS trilateral security partnership holds significant political, diplomatic and military implications both in the Indo-Pacific and beyond.



Based on the ‘enduring ideals and our shared commitment to the international rules-based order’, Australia, the UK and US have, through AUKUS, agreed to ‘deepen diplomatic, security and defense cooperation in the Indo-Pacific region’ in order to ‘meet the challenges of the twenty-first century’. That is, although not explicitly stated, the growing power and influence of China. Described as an ‘enhanced trilateral security partnership’, AUKUS is intended to ‘strengthen the ability of each to support our security and defense interests’, including through facilitating ‘deeper integration of security and defense-related science, technology, industrial bases, and supply chains’. Moreover, AUKUS will build ‘on our longstanding and ongoing bilateral ties’, and ‘significantly deepen cooperation on a range of security and defense capabilities’. For example, the US , UK and Australia operate the F-35 and P-8, whilst the UK is acquiring the E-7 Wedgetail airborne early warning and control system already operated by the Royal Australian Air Force (RAAF), the UK and Australia are procuring the Type 26 frigate (known as the City and Hunter-classes by the Royal Navy and RAN respectively), and the US Navy and RAAF are acquiring the MQ-4C Triton for the maritime intelligence, surveillance and reconnaissance (ISR) role.

The US and Australia also intend to significantly enhance bilateral defence cooperation, as the Australian Minister for Defence, Peter Dutton, stated at the Australia-US Ministerial Consultations held on 16 September 2021: ‘Australia and the United States will be significantly enhancing our force posture cooperation, increasing and deepening alliance activities in the Indo-Pacific…This will include greater air cooperation through rotational deployments of all types of U.S. military aircraft to Australia’. Further, Australia will develop combined logistics sustainment capabilities, including for submarines and surface combatants, in support of enhanced US-Australia cooperation, with Dutton adding that ‘These key activities will be complemented by conducting more bilateral exercises and greater combined exercise engagement with partners in the region’. The most vivid example of the depth of cooperation planned under the auspices of AUKUS is that of the provision of US and UK support to the development by Australia of an SSN capability (to be discussed in detail below). As the AUKUS Joint Leaders Statement explains: ‘recognizing our common tradition as maritime democracies, we commit to a shared ambition to support Australia in acquiring nuclear-powered submarines for the Royal Australian Navy’.  

The acquisition of SSNs is one component of a wider effort to ‘enhance our joint capabilities and interoperability’, with cyber capabilities, artificial intelligence (AI), quantum technologies and ‘additional undersea capabilities’ forming the initial focus for AUKUS. The Australian Prime Minister, Scott Morrison, in his press conference detailing AUKUS, in particular the decision to acquire SSNs, also announced that Australia would enhance its long-range strike capabilities. This will include the procurement of Tomahawk cruise missiles to equip the RAN’s Hobart-class destroyers, AGM-158B Joint Air-to-Surface Stand-off Missiles (Extended Range) (JASSM ER) for RAAF F/A-18 Hornets and in future, the F-35A, precision strike missiles for the Australian Army, and collaboration with the US on the development of hypersonic missiles. It is likely that Australia will seek to equip its future SSNs with a land-attack capability, such as that provided by the Tomahawk, or potential future hypersonic weapons. In this context, the US Navy intends to equip its Virginia Payload Module (VPM)-equipped Virginia-class SSNs with the Conventional Prompt Strike (CPS) missile, incorporating the Common Hypersonic Glide Body (C-HGB) payload, providing a long-range hypersonic precision strike capability from the late 2020s onwards.


Developing an Australian SSN Capability

The first major initiative under the auspices of AUKUS is the acquisition of ‘at least eight’ SSNs for the RAN, replacing a previous plan to acquire 12 French-designed Attack-class diesel-electric submarines (SSKs – the Attack-class design was derived from the French Navy’s Barracuda-class SSN). The rationale for this decision was explained in a Joint Media Statement issued by the Australian Prime Minister and Defence Minister: ‘The security challenges in the Indo-Pacific region have grown significantly. Military modernisation is occurring at an unprecedented rate and capabilities are rapidly advancing and their reach expanding. The technological edge enjoyed by Australia and our partners is narrowing’. In this context, ‘accelerating changes to regional security make conventional submarines unsuited to our operational needs in the decades ahead’ and thus necessitate investment in SSNs:

Nuclear-powered submarines do not have the same limitations that face conventional submarines on weapons storage, speed and endurance. They can stay completely submerged for many months, limiting the opportunities for detection by adversaries. As a three-ocean nation, it is necessary for Australia to have access to the most capable submarine technology available. As a nation, we are ready to take the step to pursue the most advanced submarine technology available to defend Australia and its national interests.

Moreover, as the newly established Australian Department of Defence’s Nuclear-Powered Submarine Task Force highlights:

Nuclear-powered submarines have superior characteristics of stealth, speed, manoeuvrability, survivability, and almost limitless endurance, when compared to conventional submarines. They can deploy unmanned underwater vehicles and can also carry more advanced and a greater number of weapons. These abilities allow nuclear-powered submarines to operate in contested areas with a lower risk of detection.

The RAN currently operates six Collins-class submarines, which entered service between 1996 and 2003. In 2016, Australia opted to procure under the SEA 1000 Future Submarine programme, 12 new SSKs, the Attack-class, then estimated to cost A$50 billion. However, the programme has suffered from delays, disputes over Australian industrial content, and the projected cost increasing from 50 to A$90 billion (approximately $65 billion). In January 2021, it was reported that the Australian government was becoming increasingly frustrated with the Attack-class programme and considering alternatives, namely, the acquisition of an updated version of the Collins-class, whilst the UK Secretary of State for Defence, Ben Wallace, confirmed that Australia approached the UK about acquiring an SSN capability in March 2021. As set out in the Joint Leaders Statement, an 18 month-long effort to determine the ‘optimal pathway’ for the development of Australia’s SSNs will be undertaken, and ‘leverage expertise from the United States and the United Kingdom, building on the two countries’ submarine programs to bring an Australian capability into service at the earliest achievable date’. The SSN development programme will ‘be a joint endeavor between the three nations, with a focus on interoperability, commonality, and mutual benefit’.

The development of an SSN capability will require a long-term effort and sustained investment in infrastructure and personnel, including a cadre of nuclear engineers, in particular as Australia intends to construct the submarines at the Osborne Naval Shipyard, Adelaide, potentially from around 2025 onwards. In this respect, an Australian-built SSN would not enter service until the 2030s, however, the option of leasing a British or American SSN to provide an interim capability or for training has been mentioned by the Australian Minister for Defence. There are several options potentially open to Canberra for the development of an SSN capability: the acquisition of off-the-shelf boats from the UK (the Astute-class) or the US (the Virginia-class); participation in either of the next-generation US or UK future submarine programmes, SSN(X) or SSNR; or the development of an indigenous design incorporating US and/or UK inputs. Given that the Joint Leaders Statement refers to delivering an Australian capability at the earliest achievable date, it is likely that Australia will acquire an existing design, most likely perhaps the Virginia-class.

The final two of a total of seven Astute-class boats are under construction at the BAE Systems’ Barrow shipyard and due to enter service by 2026; additional boats could conceivably be ordered for Australia. Similarly, the Virginia-class is in production. The US is currently principally building VPM-equipped boats; the VPM is a vertical launch system comprising four large diameter tubes for the launch of Tomahawk cruise missiles and other payloads, with each tube capable of accommodating seven Tomahawks. This confers a single VPM-equipped Virginia-class submarine with a capacity of 65 torpedo-sized weapons (for example, Tomahawks), in contrast to the 37 weapons of a non-VPM-equipped boat. A VPM-equipped Virginia costs approximately $3.4 billion, whilst an Astute-class boat costs around £1.5 billion ($2 billion). Bryan Clark, a Fellow at the Hudson Institute, has suggested that the Virginia-class ‘would be logical choice’, with the $66 billion previously allocated to the Attack-class programme, being sufficient for the procurement of 12 Virginia-class boats and the development of the necessary supporting infrastructure, construction and maintenance. Given the requirement to build the submarines in Australia, developing an appropriate build programme that balances acquiring the desired capability in a timely manner with wider political factors, will be key.



The development of the AUKUS trilateral security partnership is reflective of the evolving strategic environment, as the Australian Government emphasises, ‘The Indo-Pacific is now at the centre of strategic competition’, and the shift in the global balance of power from the Euro-Atlantic to the Indo-Pacific. Central to this is the growth of Chinese power, and with it, the emergence of a new US-China bipolar international system. In contrast to the US-Soviet Cold War rivalry concentrated on the East-West divide in Europe, the focus for US-China competition is East Asia, a region inherently maritime in nature. In this respect, the initial focus for AUKUS on the development of an Australian SSN and ‘additional undersea capabilities’, together with the expansion of Australia’s long-range strike potential and an enhanced US presence or access to Australian bases is intended to balance against China’s significant naval development, highlighted by the People’s Liberation Army Navy’s emergence as the world’s largest navy. As Tunsjo explains, ‘China remains the dominant power on the East Asian mainland, and the United States maintains supremacy in the maritime domain…Competition and instability will prevail’.

The Joint Leaders Statement on AUKUS refers to ‘our common tradition as maritime democracies’, whilst the UK’s Statement on AUKUS refers to both the ambition set out in Global Britain in a Competitive Age: the Integrated Review of Security, Defence, Development and Foreign Policy to deepen engagement with the Indo-Pacific and the 2021 deployment of HMS Queen Elizabeth and its accompanying Carrier Strike Group to the region. That is, maritime power will be a central element of competition in the Indo-Pacific, as the Australian Government states with regard to its acquisition of SSNs and the establishment of AUKUS, ‘This is a pivotal moment for Australia to become a more capable power in the 21st century, in line with our commitment to a global rules-based order’. In a notable statement of intent, Australia intends to operate both more SSNs and Type 26 frigates than the UK (at least eight and nine respectively, in contrast, the Royal Navy operates seven SSNs and will receive eight Type 26s).

Given the evolving US-China naval balance of power, and US commitments to countering Russia and regional powers such as Iran, it is likely that Washington seek to encourage key allies to further develop their maritime capabilities. Notably, Australia’s decision to pursue SSNs follows a January 2021 North Korean announcement that it was developing a nuclear-powered submarine, and South Korean interest in developing SSNs, whilst Japan continues to develop its submarine forces, launching in 2020 the first Taigei-class boat, which utilises lithium-ion batteries as a power source. The Taigei is due to enter service in 2022, with a further two boats planned. It is likely that Australia’s decision to acquire SSNs will further stimulate investment in the region in advanced submarine and anti-submarine warfare capabilities.

The announcement of the AUKUS partnership is intended to act as ‘a step-change that will complement our efforts to build a network of international partnerships—such as with ASEAN, our Pacific family, Five Eyes partners and like-minded partners in the region, like the Quad’. However, the new partnership and cancellation of the Attack-class programme has prompted a pronounced French response, with Paris recalling its ambassadors to the US and Australia, and a joint communique from the French foreign and defence ministers stating: ‘This decision is contrary to the letter and spirit of the cooperation which prevailed between France and Australia’ whilst ‘The American decision, which leads to the exclusion of a European ally and partner like France from a crucial partnership with Australia…which France can only notice and regret’. The communique concludes by highlighting ‘the issue of European strategic autonomy. There is no other credible path for defending our interests and values around the world, including in the Indo-Pacific region’.  

Within the region, Indonesia has also expressed concern ‘over the continuing arms race and power projection in the region’, with the Malaysian Prime Minister similarly expressing concern regarding the potential consequences for regional security. Whilst the Chinese Foreign Ministry Spokesperson stated that ‘The nuclear submarine cooperation between the US, the UK and Australia has seriously undermined regional peace and stability, intensified the arms race and undermined international non-proliferation efforts…Relevant countries should abandon the outdated Cold War zero-sum mentality and narrow-minded geopolitical perception’.

It is likely that AUKUS itself or similar minilateral arrangements will be developed as part of US-led efforts to ensure a favourable balance of power in the Indo-Pacific. Given the central role of the US-Japan alliance and the Quad, and reported Japanese interest in joining the Five Eyes alliance, together with Japan’s geostrategic position and potential, an enhanced role for Tokyo in the US Indo-Pacific alliance system cannot be dismissed. Moreover, as US-China competition evolves and intensifies, it will be accompanied by geopolitical manoeuvring on both sides as each seeks to strengthen its position vis-à-vis the other. In this context, AUKUS, rooted in the ‘Anglosphere’, provides the US with a defence and security partnership based on enduring bilateral and alliance relations, and one that can be further developed as the evolving strategic environment dictates.      

James Bosbotinis

Dr James Bosbotinis is a specialist in defence and international affairs. He has particular expertise in the study of contemporary maritime strategy, assessing naval and air force developments, geopolitical analysis, and generating understanding of the connections between maritime strategy and national policy. Dr Bosbotinis has extensive experience encompassing academic and policy-relevant research and analysis for a range of customers, including UK government bodies. He has written widely on issues including the development of British maritime strategy, maritime airpower, Russian maritime doctrine, naval and wider military (including nuclear) modernisation, and China’s evolving strategy. Dr Bosbotinis is the Book Reviews Editor for The Naval Review (the UK’s professional journal for the Royal Navy), a member of the Defence IQ Advisory Board, an Associate Member of the Corbett Centre for Maritime Policy Studies, King’s College London, and the co-CEO of JB Associates, a geopolitical risk advisory.