The Department of Defense should continue to embrace AUKUS as a bulwark of Indo-Pacific security.

On June 11, 2025, the news broke that US Under Secretary of Defense Elbridge Colby would lead a Pentagon review of the Australia-United Kingdom-United States security agreement (AUKUS). The Department of Defense has since articulated that this effort will be “an empirical and clear-eyed assessment of the initiative.” If that standard is applied, the assessment must conclude, as a similar 2025 review in London did, that AUKUS is the strongest, most effective plan for the United States to deter China’s malign behavior in the Indo-Pacific.

China certainly knows that AUKUS’ promise to accelerate the deployment of advanced defense technology by the three participating nations, including the sale of conventionally armed, nuclear-powered submarines to Australia, will counter the growing strength of its PLA Navy and missile forces in the Indo-Pacific. 

China has repeatedly complained about AUKUS in public and in private diplomatic channels, which should speak volumes about its value to Under Secretary Colby as he conducts his investigation. AUKUS, in a nutshell, will blunt China’s regional advantage that threatens the 80-year success of the free and open Pacific. 

Much of the AUKUS skepticism in the United States is premised on the misguided notion that the technology being shared and sold among the three allies will create an unacceptable drain on the US military. Since AUKUS is not a binding treaty that commits Australia and the UK to every imaginable conflict in which the United States could be engaged, skeptics argue that the cost and risks of sharing too much are unacceptable.

Under Secretary Colby himself publicly questioned the planned sale of three Virginia-class submarines to Australia last year, before re-entering the Pentagon in 2024, citing concerns that the US Navy cannot afford it. This part of the plan, developed in 2022–23 by the leadership of all three countries as part of the AUKUS “Optimal Pathway,” is essential. 

Australia operates an aging fleet of diesel submarines, which will need to be phased out in the 2030s, before its own domestic industrial base is able to replace them with new submarines. The US defense industrial base, despite criticism, is expected to have delivered 28 Virginia-class submarines by the end of 2026, since the nuclear-powered attack submarine was first commissioned in 2004. Ten additional Virginia-class boats are also under construction. Those 28 submarines are in addition to 23 Los Angeles-class fast-attack submarines and three Seawolf-class fast-attack submarines currently in the US Navy fleet. For comparison, the Chinese Navy currently operates six nuclear-powered fast-attack submarines, while the British Royal Navy operates five. 

Looking past the 2025 submarine tally, Under Secretary Colby’s review should focus on the evolving capacity of the US industrial base when Australia actually purchases its submarines in the 2030s. A key part of this equation is the massive investment by Congress in the US submarine industrial base over the last seven years, which is now coming to fruition.

Starting in 2018, Congress has invested over $10 billion in expanding the workforce, supply chains, and production facilities across the country. In addition to hiring sprees in Virginia and southern New England shipyards in the last four years, more yards in Mobile, AL, Philadelphia, PA, Tampa, FL, and Goose Creek, SC, are coming online to add 6 million new man-hours per year to boost submarine production through large-scale steel fabrication. 

Congress has slated this infusion of funding to continue in future years’ Navy budgets, recognizing that this overdue expansion of shipbuilding is a long game. The Australian Government is also playing its part in this investment, as outlined in the Optimal Pathway, having already delivered $1 billion of its committed $3 billion to the US submarine sector. 

This is not to say that the race to uplift submarine production is complete. In the United States, the Office of US Naval Reactors, the Navy’s Maritime Industrial Base office, and the Secretary of the Navy John Phelan have assessments underway, scrubbing the factory floors and waterfront dry docks to make industry work faster and more productively. Deputy Secretary of Defense Steve Feinberg also elevated oversight of this enterprise to the top of the Pentagon’s priorities through a Direct Reporting Portfolio Manager, or DRPM, which will hopefully continue this whole-of-government approach to maximizing US submarine output.

In the midst of all the speculation about the sale of submarines since June, the short-term benefits of AUKUS to the United States have been overlooked. Starting in 2023, more frequent rotations of Virginia-class submarines have been arriving and departing from the Australian naval base HMAS Stirling, located outside Perth. These rotations are a precursor to the 2027 establishment of Submarine Rotational Force-West that will maintain permanent rotational US and UK nuclear-powered submarines for years to come.

The head of the US Indo-Pacific Command, Admiral Samuel Paparo, testified before Congress in April, arguing that this forward deployment of allied fleets drastically shortens existing transit times into the South China Sea and the Indian Ocean. Consequently, China’s nonstop and often illegal efforts to control the sea and airspace will be hindered. This forward deployment will include access to in-theater submarine repairs, eliminating the need for lengthy voyages back to US facilities. This invaluable element of AUKUS provides the United States with a response and readiness advantage that cannot be overstated.

Also overlooked is the Pillar 2 component of AUKUS, which will synergize innovation among the three nations in the development of hypersonics, artificial intelligence, quantum computing, and unmanned vehicles. The Optimal Pathway correctly recognized that the three allies have their own unique expertise to share in the Pillar 2 arena.

Since AUKUS’ original announcement on September 15, 2021, its strategic and diplomatic status has survived changes of government in the UK and Australia. In the United States, congressional support is deep and bipartisan, as demonstrated by the 2023 enactment of the AUKUS legal authorities for the sale of Virginia-class submarines, with votes of 310-118 in the House and 87-13 in the Senate. This support was resoundingly reaffirmed in bipartisan Congressional letters and public endorsements of AUKUS following the news of the Pentagon’s review. 

In the coming weeks, the Pentagon review will signal to our closest allies whether all the effort and investment made to execute this extraordinary collaboration will continue. A report that endorses AUKUS, with a blueprint to strengthen its execution, will be a powerful signal to the Indo-Pacific region that our country is serious about defending the sovereignty of the region’s nation-states and the international rule of law. A report recommending the truncation or cancellation of AUKUS will have the opposite effect and be met with great rejoicing in Beijing. It is obvious that a “clear-eyed” assessment should emphatically join our closest allies and firmly endorse AUKUS.