Home / Articles / Strategic Choice: Australia’s Nuclear-Powered Submarines
In September 2021, Australia scuttled a deal with a French shipbuilder to buy 12 diesel-electric attack submarines. Instead, Australia decided to acquire at least eight nuclear-powered ones with technical assistance from the United Kingdom and the United States, as part of their new and broader AUKUS security partnership. Although the future submarines, once built, may not dramatically alter the balance of power in the Indo-Pacific, they will have a meaningful impact on Australia’s position in the region. They will surely change how other countries, most notably China, see it. Unsurprisingly, Beijing was unhappy with the decision and quickly denounced Australia for “intensifying an arms race”—an ironic accusation considering China’s far more expansive naval buildup.
Throughout the 2010s, Australia’s defense white papers expressed the country’s concerns over the worsening security situation in the Indo-Pacific and the waning dominance of its longtime security guarantor, the United States. Ultimately, Australia’s decision to acquire nuclear-powered submarines was one intended to address those concerns. Such submarines do not mean that Australia will inevitably procure or produce nuclear weapons, the pursuit of which it gave up in 1973. What nuclear reactors aboard its submarines will do is enable them to sail much farther and faster, and do so more quietly than any diesel-electric submarine can. As a result, they will be able to stay on patrol longer and offer Australia greater protection against threats from afar—the potential for which has risen with the proliferation of long-range guided missiles. Perhaps equally important, Australia’s future submarines will enable Canberra to play a bigger role in shaping regional events, rather than merely responding to them—a step forward for a country that has traditionally relied on great-power benefactors for strategic defense.
Australia’s security concerns have always revolved around the danger of isolation. Located far from its most powerful allies, Australia could be easily cut off if an adversary came to dominate the seas around it. As a senior Australian intelligence official once summed up, “Isolation in a hostile environment would cost Australia foreign policy independence and control of its trade, reinforced by threat of occupation.” But the resources that Australia has had at its disposal to prevent its isolation have long been small when compared to the enormous task of defending a continent. That problem is made even harder because the infrastructure needed to defend Australia is largely situated along its southern coasts, whereas threats to it have historically come from the north. During World War II, Darwin (in Australia’s north) was the first Australian city to come under attack by Japanese forces. Help was far away. The distance by sea between Darwin and Perth (in Australia’s southwest) is 4,180 km and between Darwin and Sydney (in Australia’s southeast) is 4,750 km.
Today, another Asian power is putting itself in a position that could enable it to isolate Australia. China’s push through the South China Sea has brought Chinese warships, armed with long-range cruise missiles, deep into the center of maritime Southeast Asia and ever closer to Australia. Indeed, the distance by sea from the South China Sea to Darwin is slightly shorter than that from either Perth or Sydney. Hence, Australia has eyed China’s naval expansion, its construction of South China Sea outposts, and its basing of new nuclear-powered attack and ballistic missile submarines in the region with consternation. Needless to say, the appearance of a Chinese navy Type 815 electronic surveillance ship near a major Australian military exercise in 2017 and the unannounced visit of three Chinese naval vessels to Sydney in 2019 did nothing to allay Australian fears.
Canberra has also watched as China pushed its Belt and Road Initiative across the central Pacific, indebting many of Oceania’s island countries to Beijing. That has made Australia worried about both China’s growing influence in the region as well as the potential for China to use the aviation and port infrastructure that it built there for something other than commercial purposes. After all, Japan tried to use the same region (then called the Caroline and Marshall Islands) during World War II to sever Australia’s sea lanes of communication with the United States. Hence, Canberra has already taken actions to counter China there: from forestalling a deal between two Melanesian countries and China’s Huawei to lay high-speed internet cables to assisting Papua New Guinea to build its naval and police capacity.
Prior to World War II, Australia depended on the United Kingdom (or, more accurately, the British Empire) as its ultimate security guarantor. Following the war, Australia turned to the United States for strategic defense throughout the Cold War and the years thereafter. But as early as 2002, Australian observers began to fret over America’s slipping dominance in the Indo-Pacific. According to them, the United States was becoming a less reliable ally for Australia—too preoccupied by its adventures in the Middle East and subsequent retrenchment to devote enough attention or resources to Indo-Pacific security.
Thus, in the late 2000s, some Australian strategic thinkers began to believe that a change in Australian foreign policy was in order. With Australia’s economy increasingly tied to China’s after the turn of the millennium, they argued that Australia should move toward a position of greater balance or even neutrality between China and the United States. And that was the direction in which Australian public opinion seemed to drift for most of the 2010s.
But in 2018, momentum toward that end staggered as a growing number of revelations about Chinese interference in Australian society, including its political system, came to light. Making matters worse, China soon started to engage in a new pugnacious style of diplomacy that would become known as “Wolf Warrior diplomacy.” Rather than reassuring Australians, Chinese diplomats seemed to go out of their way to make them apprehensive with threat-laden polemics. And finally, as if to confirm Australian unease, Beijing then sought to punish Australia with boycotts and trade disruptions for its support of an investigation into the origins of the COVID-19 pandemic. Not surprisingly, Australian affinity for China abruptly cooled.
China’s behavior reminded Canberra of how quickly Beijing could turn from being a partner bearing trade opportunities into an adversary bearing threats. The strategic implications for Australia were clear: It could not count on China’s “peaceful rise” for its security. Australia would have to do more for its own defense. In terms of military procurement, that meant Canberra had to do its best to satisfy its navy’s requirements for Australia’s future submarine fleet. That, in the end, is what motivated Australian leaders to select a nuclear-powered design over a conventionally powered one for the submarines in that fleet.
Longer Sea Legs
For Australia, the importance of its future submarines is difficult to overstate. They will not just replace its existing Collins-class diesel-electric attack submarines, but also almost certainly be Australia’s frontline forces in any future naval conflict, considering the vulnerability of surface warships to the combination of increasingly pervasive sensors and accurate guided missiles. While the precise requirements for Australia’s future submarine fleet will remain classified for years to come, one can glean from the comments of Australian legislators their broad strokes. The requirements appeared to have centered on three key features: power, range, and speed.
Canberra settled the requirement for power early on. Given Australia’s aim to field what it referred to as “regionally superior” submarines, it quickly selected a suite of largely American submarine combat information, sensor, and weapon systems to deliver that power. The far bigger challenge was meeting the requirements for range and speed. To overcome Australia’s vast maritime distances, those requirements likely called for a very long maximum range and a very high cruising speed, both of which are hard to satisfy without nuclear propulsion. In 2017, former Prime Minister Tony Abbott said as much when he acknowledged that he should have pushed for nuclear-powered submarines during his tenure from 2013–2015 and regretted not more robustly challenging the Australia’s “nuclear no-go mindset.”
The operational advantages of nuclear-powered submarines have long been clear. The biggest one is probably their unlimited range. They never have to be refueled during their 30- to 40-year service life. Another advantage is their ability to stealthily sail at high speeds, rapidly reaching trouble spots. A nuclear-powered submarine can transit from Australia’s Stirling naval base, rumored to be the homeport for Australia’s future submarine fleet, to Darwin in 3.1 days at an average speed of 30 knots. Even the most advanced diesel-electric submarine would require at least 7.2 days at an average speed of 13 knots to traverse the same distance, and it would have to repeatedly surface to recharge its batteries.
Moreover, once a nuclear-powered submarine arrives on station, it can patrol far longer than its diesel-electric counterpart, especially in distant waters. If patrolling the South China Sea, a nuclear-powered submarine could stay on station for 77 days, while its diesel-electric counterpart could do so for only 11 days, according to one study. Even close to Australia’s northwest coast, a nuclear-powered submarine could still patrol 2.5 times longer than a diesel-electric one. In short, nuclear-powered submarines would greatly improve Australia’s the ability to defend its entire continent.
Even so, nuclear-powered submarines presented Australia with three problems. First, they are expensive to design, build, maintain, and operate. They would require specialized personnel, infrastructure, and training facilities that Australia currently does not have. Those inadequacies were well detailed by Australia’s then-defense minister in 2017. Second, they would take longer to construct. Without an existing domestic nuclear industry, it would take time for Australia to develop the capacity to produce the necessary components for nuclear reactors. That could delay the introduction of Australia’s future submarines by as much as a decade. And last, becoming a nuclear power, even one without nuclear weapons, could strain Australia’s relations with its neighbors, like Indonesia and Malaysia.
Thus, Australian leaders focused their attention on diesel-electric attack submarine designs during the early 2010s. Unsurprisingly, none of the designs turned out to fully meet the Australian navy’s requirements for range and speed. Eventually, in 2016, Canberra decided to hedge its bets and signed a deal with a French shipbuilder, DCNS, for a hybrid design which combined the hull of France’s Barracuda-class nuclear-powered attack submarine with a new type of diesel-electric propulsion system. That kept Canberra’s options open; the hybrid design would enable Australia to replace the conventional propulsion system with a nuclear one, if needed, in later-build boats. Indeed, Australia’s 2016 Defence White Paper made it clear that Canberra would periodically review the features of its submarine acquisition program and change direction “based on the strategic circumstances at the time and developments in submarine technology.”
Australia’s deal with DCNS caught Japan by surprise. Earlier, a pair of Japanese shipbuilders had offered Australia a design for a modified version of Japan’s Soryu-class diesel-electric attack submarine, and appeared close to securing Australia’s submarine contract at the start of 2016. But, as it turned out, the French hybrid design won out. In hindsight, Canberra’s choice made sense; the requirements for Australia’s future submarines always pushed Canberra toward a design that included nuclear propulsion in some fashion, a feature that the Soryu-class design could never accommodate. And so, after the United States dropped its hesitation to the installation of American submarine combat systems into European-built submarines, Canberra felt free to pursue the French option.
However, in the half decade after Australia signed the deal with DCNS (now called Naval Group), problems with the retrofit of a diesel-electric propulsion system into the hull of a nuclear-powered submarine caused repeated cost overruns and schedule delays. Meanwhile, Canberra grew frustrated with Naval Group’s failure to invest enough in local Australian suppliers. Worst still, the estimated total cost for Australia’s future submarine program had soared from A$50 billion to A$90 billion. In fact, the estimated total cost and time needed to build the program’s 12 diesel-electric attack submarines rose so high that they exceeded those required to buy a similar number of American Virginia-class nuclear-powered attack submarines (albeit without their supporting infrastructure). By early 2021, the French-led submarine program was clearly was in serious trouble.
Hence, when the United Kingdom and United States offered to provide Australia with the technology needed to build nuclear reactors for its future submarines as part of their AUKUS security partnership, Australian leaders almost assuredly saw it as an opportunity to acquire the submarines that they always wanted at a unit cost possibly lower than that of their troubled diesel-electric submarine program. To be sure, building nuclear-powered submarines will still be a challenge for Australia. But the ease with which Canberra made the switch was impressive. Surely, some level of agreement between Australia’s two major political parties was important. The advocacy of Tony Abbott, a Labor Party leader, for nuclear-powered submarines over the last four years likely helped lay the groundwork for Australian Prime Minister Scott Morrison, the head of the ruling Liberal-National Coalition, to act as quickly as he did without major parliamentary opposition.
No doubt, nuclear-powered attack submarines will once and for all satisfy the Australian navy’s requirements for its future submarine fleet—requirements that were crafted to meet the practical needs of defending a continental country in an age of ever longer-range guided weapons. If all eight nuclear-powered attack submarines that have been mentioned are built (probably in the late 2030s), they will enable Australia to maintain a continuous presence in the waters off its northern coasts as well as give Australian leaders a much wider range of options in responding to possible future crises, even on short notice.
But beyond its operational impact, Canberra’s decision to construct nuclear-powered submarines also has a strategic one. The long reach of its future submarines will give Australia the ability to influence events across the Indo-Pacific. That ability, in turn, will give Canberra a bigger voice in regional decisions that affect Australian security, clearly a boon to it in the long run. Naturally, that ability will also change how other countries see Australia. Some, particularly Indonesia and Malaysia, may come to regard it as just another external power rather than a country that aspires to be “fully part of the region.” On the other hand, China might be given second thoughts about viewing (and treating) Australia with disdain, as Beijing has done in recent years.
Certainly, Australia’s future nuclear-powered submarines are not a cure-all. But they do enable Australia to better ensure its continued political and economic independence in an increasingly uncertain security environment where a potential adversary continues to grow ever stronger. That may be as much as any country can expect from the adoption of any single sort of military hardware. Now, if only Australia can keep its reinvigorated submarine acquisition program on track.
The views expressed in this article are those of the author alone and do not necessarily reflect the position of the Foreign Policy Research Institute, a non-partisan organization that seeks to publish well-argued, policy-oriented articles on American foreign policy and national security priorities.
 Kirsty Needham, “Australia to build eight nuclear-powered submarines under new Indo-Pacific pact,” Reuters, Sep. 16, 2021.
 Australia Department of Defence, 2020 Defence Strategic Update (Canberra: Commonwealth of Australia, 2020), pp. 11-17; Australia Department of Defence, 2016 Defence White Paper (Canberra: Commonwealth of Australia, 2016), pp. 39-65; Australia Department of Defence, 2013 Defence White Paper (Canberra: Commonwealth of Australia, 2013), pp. 7-21; and Australia Department of Defence, Defending Australia in the Asia Pacific Century: Force 2030 (2009 Defence White Paper) (Canberra: Commonwealth of Australia, 2009).
 A. D. McLennan, “Australia’s Security Dilemma,” Policy, Vol. 18, No. 2 (Spring 2002), p. 21.
 Sam Roggeveen, “China’s New Navy: A short guide for Australian policy-makers,” Strategic and Defence Studies Centre at the Australian National University The Centre of Gravity, May 2018, pp. 5-8.
 Denghua Zhang, “Chinese Concessional Loans: Part 2 — Pacific Indebtedness,” College of Asia and the Pacific at the Australian National University In Brief, 2018/29; and Denghua Zhang, “China’s Military Engagement with Pacific Island Countries,” College of Asia and the Pacific at the Australian National University In Brief, 2020/22.
 Ashley Townshend and Brendan Thomas-Noone, Averting Crisis: American Strategy, Military Spending and Collective Defence in the Indo-Pacific (Sydney: United States Studies Centre at the University of Sydney, Aug. 2019), pp. 8-25; Malcolm Fraser, “America: Australia’s Dangerous Ally,” National Interest, Dec. 16, 2014, http://nationalinterest.org/feature/america-australias-dangerous-ally-11858; and Ian Storey, “Assertive China gives Australia cause for concern,” Jane’s Intelligence Review, Aug. 2002, pp. 12-14.
 Albert Palazzo, “From Dependency to Armed Neutrality: Future Options for Australian National Security,” Strategic and Defence Studies Centre at the Australian National University The Centre of Gravity, Nov. 2018; Jane Perlez and Damien Cave, “Australia Questions Global Allegiances,” New York Times, Dec. 4, 2017, p. A8; Andrew Browne, “Economic Reality Puts Australia in a Corner,” Wall Street Journal, June 17, 2014; James Reilly, “Counting On China?: Australia’s Strategic Response to Economic Interdependence,” Chinese Journal of International Politics, Vol. 5, No. 4 (Winter 2012), pp. 369–394; Hugh White, “Power Shift: Rethinking Australia’s Place in the Asian Century,” Australian Journal of International Affairs, Vol. 65, No. 1 (2011), pp. 81-93; and Hugh White, “Power Shift: Australia’s Future Between Washington and Beijing,” Quarterly Essay No. 39, (2010), pp. 1-74.
 Damien Cave, “Suddenly, the Chinese Threat to Australia Seems Very Real and ‘Inescapable’,” New York Times, Nov. 30, 2019, p. A9; and Damien Cave and Jacqueline Williams, “In Broad Legislation, Australia Bans Foreign Political Interference,” New York Times, Jun. 29, 2018, p. A5.
 Australia Department of Defence, 2016 Defence White Paper (Canberra: Commonwealth of Australia, 2016), p. 19.
 Jim Thomas, Zack Cooper, and Iskander Rehman, Gateway to the Indo-Pacific: Australian Defense Strategy and the Future of the Australia-U.S. Alliance (Washington, D.C.: Center for Strategic and Budgetary Assessments, 2013), p. 33.
 Australia Department of Defence, 2016 Defence White Paper (Canberra: Commonwealth of Australia, 2016), pp. 91, 115.