Nuclear Submarine Deterrence for Australia’s Strategic Defense
Introduction
In the early 1990s, Australia acquired a new class of Diesel-Electric Submarines which would come to be known as the Collins-class. This class is based on the Swedish Kockums Type 471. The main purpose of this acquisition was to ensure that Australia had a capability that could project a coherent power into Southeast Asia and the Southwest Pacific with a two-ocean navy.
This essay argues that nuclear propulsion has become central to submarine warfare because of endurance, survivability requirements, and deterrence missions. The historical evolution of the U.S. SSN program shows this strategic logic, which explains why nuclear-powered submarines remain central to modern deterrence strategies such as AUKUS. It shows that many of the critical discussions of the AUKUS program miss the longer history of defense acquisition in Australia. It proves this by exploring the evolution of the United States National Security Strategies for the last 40 years. It then shows how the longer history of the United States Nuclear Submarine program evolution, spanning the Nautilus, Sturgeon, Los Angeles, Seawolf, and the Virginia-class Submarines, have represented deterrent theory in practice.
These classes of submarines have taken part in a range of missions which apply to Australia’s growing strategic need, which include ISR, land-based power projection, and commercial fleet protection.
A few clarification points of terminology used throughout this essay will be used as following:
- SSK – Submarine, Hunter-Killer (diesel-electric)
- SSN – Submarine, Nuclear-Powered
- SSBN – Subsurface Ballistic Nuclear Submarines
- ISR – Intelligence Surveillance and Reconnaissance
History of the Collins Class
In 1993, Australia launched the Collins class Diesel-Electric submarine into service. This was done with the goal of “reducing tensions and removal of threat” which is in stark contrast to the geostrategic environment Australia finds itself in thirty-three years later. As discussed in the previous essay, the Australian National Defense Strategy has shifted towards denying and deterring Australia’s enemies from projecting power against Australia.
As Australia pivots to nuclear propulsion, key questions arise:
- What national security/strategic imperatives require the acquisition, and
- how does nuclear propulsion contribute to Australia’s own deterrence and forward projection capabilities?
The Collins-class was built off the Swedish Kockums Type 471 to replace the aging Oberon-class submarine, just as AUKUS had been a highly politicized process. The then Deputy Prime Minister Kim Beazley changed Australia’s strategic direction to project coherent strategic capability into Southeast Asia and the Southwest Pacific with a two-ocean navy.
Additionally, the Royal Australian Navy (RAN) doctrine during this period had been shaped by longstanding cooperation with United Kingdom and United States nuclear-powered submarines. However, the threat environment facing Australia has changed between 1993 and 2026, particularly due to the People’s Liberation Navy’s (PLANs) expanding presence in the South China Sea and the broader Indo-Pacific region.
When examining the threat environments between the two periods of 1985–1990, and 2020-onwards, it will become apparent that the need for nuclear-powered submarines is a strategic reality.
Threat Environment: 1985 – 2016
The United States National Security Strategy (NSS) in 1986 focused on three distinct pillars; one of these pillars focused on the forward deployment of forces and containment of Soviet military expansion, especially Soviet nuclear delivery systems. These systems included SSBNs, which served as undetectable launch platforms for intercontinental ballistic missiles.
The NSS had accounted for the threat environment, as the Soviet Armed Forces strategy for the periods between 1961-1990 had a focus on preparation for an all-out nuclear war with the United States and NATO, except for 1981-1985 where they were preparing for a conventional war.
The Los Angeles-class SSNs, also known as the 688 class, entered service between 1976 and 1996 with a total of 62 being procured to serve as a counter to the Soviet SSBNs. Their extended endurance and ability to conduct long-duration patrols reinforced deterrence by enabling persistent tracking of adversary assets.
In 1993, two years after the collapse of the Soviet Union, the same year the Collins-class launched, the United States released its National Security Strategy with a core focus on security through strength, with similarities to the 2024 Australian National Defense Strategy.
The NSS places particular focus on strategic deterrence and defense through maintaining highly trained and technologically sophisticated conventional and unconventional forces, forward presence, and crisis responses. Where the 1985 and 1993 strategies diverge is that the United States was no longer preparing for an all-out nuclear or conventional war with the Soviet Union, but rather planned to deny the exploitation of vulnerabilities in its defenses.
Threat Environment: 2021 – Onwards
The 2022 National Security Strategy however, shows that the post-cold war environment is over and has shifted towards an era of strategic competition between democracies and autocracies. The NSS shifts the focus from “strategic deterrence” to integrated deterrence, meaning an integration across domains (e.g. land, air, maritime, cyber, and space), along with integration with allies and partners. The NSS acknowledges that Americas allies are on the front of the PRC’s coercion and expresses an interest in keeping peace and stability in the Taiwan strait.
The 2026 NDS returns to the hallmarks of the 1985, 1993, 2016, and 2022 National Security strategies by emphasizing security through strength and increasing burden sharing on allies, all of which, in concept, have still been focused on the general concept of deterrence through capable and integrated platforms.
While U.S. policy appeared to fluctuate across administrations, the underlying strategic logic of deterrence has remained remarkably consistent. Changes in political leadership have altered how this logic is expressed, not the core principles that sustain it.
Adding to the argument relating to the debate of AUKUS, some of the political commentary has raised concerns about Australian sovereignty. Both Garth Evans and Paul Keating framed the acquisition of the technology as an “abdication of sovereign agency”—that the sharing of the technology would result in Australia being drawn into wars led by the United States.
The problem with this argument is that Australia has a long history of acquiring advanced U.S. military technology—such as the F-18, F-35, F-111, and HIMARS without ever being compelled to enter a conflict on behalf of the United States. For instance, Australia’s participation in Operation Desert Shield was driven by its commitment to upholding UN sanctions and the rules-based international order, not by pressure from Washington.
Australia was requested to participate in the Gulf War by President Bush, but it was at the end of a process that was initiated by the State Department. Labor Prime Minister Bob Hawke told parliament the invasion provoked a crisis that was likened to the Second World War.
The justification given for Australia’s participation in Operation Desert Shield centered on Australia’s identity as a principled democratic nation, but also, its own vital interests through its trading partners, and the potential impact it could have on oil prices.
The 2024 Australian Defense Strategy prioritizes equipping the Australian Defence Force with integrated capabilities, aligning closely with the United States’ posture—much as it did during Operation Desert Shield—and enabling the RAN to contribute to Indo-Pacific security through AUKUS.
The national security imperatives are beyond looking at the worsening strategic environment, but ensuring the use of nuclear propulsion is suitable for a range of tasks in both a conventional and irregular sense. Australia’s strategic environment favors a mature, integrated submarine ecosystem with a long operational history.
In clarifying what this means, U.S. Army FM-3-0 Operations shows that the object of war is to impose a competing nation’s will on another through either Conventional or Irregular Warfare:
- “Conventional warfare is a violent struggle for domination between nation-states or coalitions of nation-states (ADP 3-0). Conventional warfare is generally carried out by two or more military forces through armed conflict.”
- “Irregular warfare is the overt, clandestine, and covert employment of military and non-military capabilities by state and non-state actors to achieve policy objectives other than military domination of an enemy, either as the primary approach or in concert with conventional warfare.”
- In practice, a threat in conventional and irregular warfare may involve nation-state adversaries and/or non-state state actors using a mixture of regular, irregular, terrorist, or criminal elements all unified to achieve a mutually beneficial effect.
“Mutually beneficial effects” can be described as either the destruction, domination, or disruption of an enemy’s ability to communicate with their forces; thereby achieving the political objective.
If modern conflicts combine both conventional and irregular forms, then platforms that can operate for extended periods remain survivable, and adaptation to multiple missions becomes strategically essential. The history of the U.S. nuclear-submarine program shows that nuclear propulsion provides exactly these capabilities, meeting the demands of this blended threat environment. The strategic requirements of this are that the capability must be able to fulfil multiple roles beyond simple anti-area/access control (A2/AD). This, when looking at how the United States Navy (USN) used the SSNs during the Cold War, shows that nuclear-capable submarines produced under the AUKUS treaty are a strategic necessity for Australian requirements.
History of the SSN in the United States
In describing mission profiles, most analyses of the AUKUS program tend to overlook the fact that historically, submarine warfare has contributed heavily to intelligence, surveillance, and reconnaissance (ISR). This was especially true during the Cold War, given that the whole premise of nuclear propulsion was to introduce a capability that would survive for longer periods of time, in both friendly and contested waters, than SSKs.
After the Second World War, much of the American submarine (SSK) technology had evolved with help from German U-Boat technology, this included the improved designs of the snorkels and the batteries.
The USS Cochino SS-345, a Balao-class submarine, was converted into a Greater Underwater Propulsion Power (GUPPY) II design in 1949. The GUPPY II Program, with the help of German U-boat technology, modernized a WWII submarine by introducing streamlined improvements across the bow and superstructure, changing the battery configuration from two main batteries with 126 cells each to four main batteries with 126 high-capacity cells to improve endurance underwater.
Nonetheless, the U.S. Navy still had an endurance issue. Adm. Hyman Rickover solved this with nuclear-propulsion with the introduction of the USS Nautilus (SSN-571) during ISR missions.
ISR missions, in relation to SSNs, can remain in-place, undetected near an adversary’s coast, collecting information about Electronic Intelligence (ELINT) on adversary military frequencies, sending special operations forces without detection. Additionally, SSNs, in this capacity, can get close to targets and feed targeting information for a coordinated strike.
Contextually, during the Cold War, SSNs such as the Nautilus and later the Los Angeles-class and Seawolf-class submarines were used for such mission profiles. Then the Virginia-class, which is delivered under Pillar 1 of AUKUS, was used in a contemporary setting of ISR missions, along with the ability of power projection using Tomahawks.
Sea of Okhotsk – Electronic Intelligence
The USS Halibut (SSGN, Later SSN-587) was a nuclear-powered guided missile submarine-turned-special operations platform, and the USS Parche (SSN-683) was a Sturgeon-class SSN. Both were used by the USN in the late stages of the cold war to perform ELINT collection and collect fragments of Soviet ICBMs.
Hulls in the Sturgeon-Class during the 1970s of the Carter Administration, SSN-678, 680, and 681 all performed large-scale surveillance operations by listening to ELINT near the Soviet Union, whereas the Parche mission was for cable-tapping in the Sea of Okhotsk.
The Parche underwent an overhaul at Mare Island where a 100ft section was installed, giving it the ability to deploy divers or special equipment. For five years, the Parche snuck into the shallow waters of The Sea of Okhotsk to tap Soviet-military communications between two big bases.
The success of the mission underscores the point regarding survivability and endurance capability. Operation Ivy Bells as it was called was only made known to the Soviets by the NSA agent Ronald Pelton, who spied for the Russians between the 1970s and 1980s.
Los Angeles Class and Soviet SSBNs
By 1984, following the success of the wiretapping of communications in the early 1970s, the USN was able to conclude that the Soviets were preparing for a nuclear first-strike. This was because the Soviets had planned to move their Typhoon and Delta-class SSBNs into safe bastions; in general, bastions can be thought of as places which are sanctuaries for the SSBNs protected by SSNs.
What it showed was that the Soviets were close to achieving nuclear parity to launch a second strike given advances in the technological design of the ICBMs and submarine hull design which offered greater protection for the submarines; the USN concluded that if war did break out, they would have to hunt Soviet SSBNs and SSNs underneath the arctic ice.
By 1987, the SSN program had become so intrinsically linked to the strategic success of the deterrence aspect of the strategy, that the U.S. Navy had chased a cluster of Soviet Victor III Submarines from the U.S. East Coast, along with continuing their surveillance missions of the Soviet Union. This occurred at a time when the Los Angeles-class had become an integral part of the mission. Several platforms, including SSN-716, 707, 672, and 701, operated out of the North Pacific for seven months conducting surveillance operations.
By the 1990s, Secretary of State James A. Baker proclaimed that the Cold War had ended, as both the United States and the Soviet Union had called for an arms embargo on Iraq, thus beginning a shift in defense strategic policy away from peer-to-peer competition to a focus on regional conflicts in the Middle East.
When war broke out in the Persian Gulf (Operation Desert Shield) the role of SSNs had shifted to strikes against inland targets using Tomahawks by the USS Louisville (SSN-724) and the USS Pittsburgh (SSN-720). Other attack submarines (U.S. and allies) fulfilled a different role, protection of cargo ships in the Mediterranean and war supplies.
The role of surveillance in the SSN program had not come to a full conclusion as Iran had taken the delivery of three Soviet-Made Kilo SSKs and had boasted that they fully intended to use the platforms to take control of the strait of Hormuz. This was enough to warrant the U.S. Navy to send the USS Topeka (SSN-754) in November of 1992, concluding how an SSK could compare with the Russian Akula SSN.
The navy subsequently concluded that 25 percent of the surveillance missions within the SSN program were directed at Russian waters, and the remaining 75 percent were directed at the Middle East.
During this time, the Clinton administration sought a draw down on United States Armed Forces and allowed the construction of the three new Seawolf-Class SSNs, rather than to halt it at once. The reason for doing this was that he wanted to prevent the industrial base that built the submarines from shriveling up.
The administration then gave permission to build a new class of attack submarines, smaller, cheaper, and more versatile than the Los Angeles and Seawolf-class. The Virginia-class was to be designed for new missions in shallow, regional waters.
As AUKUS prepares to build a jointly designed nuclear submarine capability, it will join as an example of how strategic imperatives necessitated a change in deterrence and alliance posture.
Conclusion
During the 1990s, Australia acquired the Collins-class submarine as an effort to reduce regional tensions and to have a capability that could project power into southeast Asia and the Southwest Pacific with a two-ocean navy. In this period, the RAN had already begun to learn how to operate alongside U.S. and U.K. operated nuclear submarines.
During the periods of 1985 to 2016, the United States NSS focused on the core idea of strategic deterrence and defense through maintaining a highly trained and technologically sophisticated conventional and unconventional force.
Submarine warfare has long centered on ISR, a role strengthened by the shift from diesel‑electric to nuclear propulsion during the Cold War. Early U.S. upgrades, such as the GUPPY II program, improved underwater endurance, but true long‑range, covert capability emerged with nuclear-powered submarines like the USS Nautilus.
SSNs could remain undetected near adversary coastlines, collect electronic intelligence, deploy special forces, and support precision strikes. Throughout the Cold War, platforms including the Los Angeles, Seawolf, and later Virginia-class conducted complex ISR missions, such as cable‑tapping in the Sea of Okhotsk by the USS Halibut and Parche. These missions demonstrated the survivability and endurance nuclear propulsion provided. After the Cold War, SSNs shifted toward regional conflict roles, from Tomahawk strikes in Desert Shield to monitoring emerging threats like Iran’s Kilo submarines. This historical evolution underpins AUKUS, illustrating how strategic imperatives consistently drive nuclear‑submarine development and allied deterrence.
