The US decision to transfer three in-service Virginia-class nuclear attack submarines to Australia instead of the previously planned mix of one new Block VII boat and two used Block IV vessels marks a major shift in the AUKUS program, one that raises questions not only about capability and cost but also about the partnership’s deeper strategic purpose.
The announcement was made last week on the sidelines of the International Institute of Strategic Studies (IISS) Shangri-La Dialogue in Singapore, with US Defense Secretary Pete Hegseth, Australian Defense Minister Richard Marles and UK Defense Secretary John Healey announcing the major revision to the AUKUS acquisition plan.
This strategic pivot aims to streamline Australia’s naval transition by simplifying supply chain management, operational logistics and maintenance requirements while maximizing cost efficiencies.
By avoiding the complexities of simultaneously managing four distinct submarine classes, including their existing Collins-class and the upcoming joint SSN-AUKUS design, Australia intends to establish a more manageable fleet.
The decision comes amid scrutiny of US domestic shipbuilding capacity, which currently produces 1.3 attack submarines annually, well below the target rate of 2.33. To mitigate these industrial strains, Australia is financially contributing to the US industrial base and deploying hundreds of personnel for maintenance training at Pearl Harbor.
The ministers also launched a complementary program for uncrewed undersea vehicles under AUKUS Pillar II to co-develop interchangeable payloads and surveillance technologies, beginning in 2027. More broadly, the revised deal raises questions about whether AUKUS is ultimately about submarines or strategic access.
The transfer of in-service Virginia-class submarines to Australia raises several issues. As noted by Peter Jennings in an article this month in The Australian, acquiring in-service Block IV Virginia-class submarines rather than new variants creates severe financial and operational uncertainties for Australia.
Jennings notes that these submarines, engineered for a 33-year lifespan, will have significantly shorter service lives upon delivery in the 2030s, with the first unit likely retaining only 21 years of service.
Crucially, he adds that Block IV submarines require three major overhauls during their operational cycle, leaving Australia facing tens of billions of dollars in potential costs and extensive downtime, depending on whether the US completes these scheduled refits before transfer.
There’s also the issue of just how much control Australia has over its nuclear submarine project with the US. Albert Palazzo, in an article this month for The Conversation, notes that the revised AUKUS deal exposes deep strategic inequalities, rendering Australia a victim of a “bait and switch.”
Palazzo notes that by substituting a promised new Block VI vessel with a third second-hand Block IV submarine, the US significantly reduces Australia’s anticipated naval firepower. He also points out that the agreement gives the US unilateral authority to modify or cancel the transfer, pocketing Australia’s non-refundable US$2 billion manufacturing contribution.
He stresses that the AUKUS arrangement underscores the alliance’s commitment to US strategic interests — specifically securing a submarine base at HMAS Stirling — while forcing Australia to absorb structural risks with minimal leverage.
If so, China’s expanding undersea reach may help explain why such access has become increasingly valuable to the US. In a March 2026 statement for the US-China Economic and Security Review Commission (USCC), Andrew Erickson detailed a massive expansion of the People’s Liberation Army Navy (PLAN) submarine force, driven by President Xi Jinping to counter US undersea advantages.
According to Erickson, China is leveraging massive naval industrial capacity and Russian technology transfers to shift toward an all-nuclear-powered fleet.
He notes key developments such as the Type 093B nuclear-powered guided-missile submarine (SSGN) with land-attack capabilities, the construction of advanced Type 095 SSNs and Type 096 nuclear ballistic-missile submarines (SSGNs) and the fielding of the JL-3 submarine-launched ballistic missile (SLBM), capable of reaching the continental US from bastions in the South China Sea.
Regarding submarine production, Henry Boyd and Tom Waldwyn note in a February 2026 report for the International Institute for Strategic Studies (IISS) that China significantly accelerated its production of nuclear-powered submarines at the Bohai Shipbuilding Heavy Industry Co. shipyard in Huludao between 2021 and 2025.
Boyd and Waldwyn note that following a major facility expansion, China surpassed the US in both launch numbers and combined tonnage during this period. They point out that, driven by an estimated “1+2” annual output, China launched its seventh and eighth Type-094 SSBNs alongside up to nine Type-093B SSGNs equipped with advanced anti-ship missiles.
In terms of sheer numbers, Defense Security Asia reported in January 2026 that China operates 32 nuclear-powered submarines, surpassing Russia’s fleet of 25-28 units, while still lagging behind the US’s 71-strong fleet.
More important than fleet size, however, may be China’s growing ability to operate farther from home waters. In parallel with ramping up nuclear submarine production, China may be mapping the undersea battlespace for future submarine operations.
A detailed Reuters investigation from March 2026 mentions that China’s extensive undersea mapping across the Pacific, Indian, and Arctic oceans prepares the battlespace for submarine warfare, directly enabling force projection beyond the First Island Chain.
Reuters notes that China uses dozens of civilian research vessels under its “civil-military fusion” policy and deploys advanced acoustic sensors, buoys, and subsea arrays to collect critical real-time hydrographic data, including salinity, temperature, and currents.
The report states that by masterfully charting underwater topography near US and allied hubs such as Guam and Taiwan, China provides its fleet with precise navigation, optimized sonar, and the concealment necessary to evade detection and project strategic power across the wider ocean. Those trends increase Australia’s strategic value as a hub for US and allied undersea operations.
Those capabilities may have been vividly demonstrated during China’s February 2025 live-fire exercises in the Tasman Sea, with a high likelihood that a nuclear-powered submarine was part of the three-ship flotilla for at least part of its journey.
Placing China’s nuclear submarine fleet within a broader strategy, US Vice Admiral Richard Seif, in a March 2026 USCC testimony, notes that China’s strategy has shifted from coastal defense to regional denial and control.
Seif says that to protect its strategic interests, China employs an anti-access/area denial (A2/AD) approach, aiming to restrict US freedom of movement and raise the costs of intervention during a crisis.
He says this strategy challenges US undersea advantages by fielding a modernized fleet of SSGNs capable of launching long-range, submerged land-attack cruise missiles. He notes that these submarines are complemented by an “Underwater Great Wall” of seabed sensors, automated networks, and anti-submarine warfare assets, narrowing the US stealth margin at critical regional chokepoints.
Viewed through a geopolitical rather than procurement lens, AUKUS may not primarily be about providing Australia with nuclear-powered submarines, but about securing US access to Australian bases and anchoring a strategic bridge between the Second and Third Island Chains.