AUKUS

The short version

Eight submarines, $368 billion, arriving after the decade of risk.

AUKUS is a 2021 agreement between Australia, the United Kingdom and the United States under which Australia acquires nuclear-powered attack submarines. Australia buys three second-hand American Virginia-class boats from 2032, then builds a new British-designed SSN-AUKUS class in Adelaide, with the first Australian-built hull expected in the 2040s. The headline cost is $368 billion to the mid-2050s.

This page is the plain-terms entry point. Each claim below is carried in full by a memo.

01 — What it costs

$368 billion to the mid-2050s on the current estimate, which already carries a 50 per cent contingency. On the escalation rates of the two most comparable programmes — the British Astute class at about 30 per cent over, and the French Attack class that Australia itself cancelled after its price climbed from roughly $50 billion toward $90 billion before a hull was laid — the trajectory runs to $480–650 billion.

About $11 billion is already spent or committed, much of it offshore and non-refundable, with no submarine in the water. The full accounting is in The AUKUS Cost Blowout — Extended, with a five-page version at the Summary.

02 — What we actually get, and when

All three Virginia-class boats are now to be second-hand. They are Block IV hulls, first commissioned from 2020, transferred in 2032, 2035 and 2038 — six to fifteen years of a 33-year design life already spent. The reactor cannot be refuelled, so the hull retires when the core is exhausted.

The Australian Submarine Agency says each will arrive with more than twenty years remaining; independent analysts, noting the American shortfall, expect older hulls and closer to fifteen. The new-build boat that would have served into the 2060s was dropped in 2026. The engineering case against the class itself is in Building the Sub to Nowhere.

03 — What a US president can withhold

The transfers are conditional. United States law requires a serving president to certify that releasing each boat will not degrade American undersea capability — against a US build rate of roughly 1.3 submarines a year when 2.33 are needed, with two a year not expected until about 2032, the year the first transfer is due.

A capability that a foreign head of state can decline to hand over is not a sovereign capability. The consequences of that dependence are assessed in America First, Australia Loses.

04 — What is already being built here

HMAS Stirling, on Garden Island off Rockingham in Western Australia, is being expanded at a cost of up to $8 billion to host Submarine Rotational Force – West from as early as 2027: one British and up to four American nuclear submarines operating from Australian soil.

The United States established Naval Support Activity Stirling — a US Navy shore command on the base — in May 2026, and reactivated Submarine Squadron 3 to run the boats. The US Navy expects about 2,300 Americans in Western Australia by 2030, including families. HMAS Stirling's own Australian complement is roughly 2,300. The sovereignty question that raises is set out on the AUASIA page.

05 — What it does not do

A conflict between interdependent economies is decided by supply lines, not fleet battles. Three sea lanes have been closed to commerce in three years — Hormuz, the Red Sea, the Black Sea — and no navy reopened any of them; the evidence is in The Proof of the Hormuz Pudding.

Australia imports about 90 per cent of its refined fuel on foreign ships, holds about 30 days of diesel onshore, and owns no product tankers. Submarines do not refine fuel, generate power, make fertiliser or repair a turbine, and they cannot make an insurer write a policy for a ship. The Island Castle measures both the submarine pathway and the alternative against what has actually decided sieges for three thousand years.

06 — What we propose instead

Not cancellation — redirection. The yards, trades and industrial base the programme would consume are what a sovereign build needs: fuel and energy made here, manufacturing, the continental corridor, the subsea corridor network, and a real defence of the continent under Australian command.

The programme is set out in full on the AUASIA page, and the case against the current plan on the Defence page.