The United States has assigned a nuclear-powered attack submarine to a rotating force based in Western Australia, marking a significant step in the AUKUS defence partnership between the US, Australia and the United Kingdom.
The 377-foot USS Colorado, a Virginia-class submarine equipped with land-attack missiles and advanced torpedoes, is expected to sail to the Australian base in late 2027, according to officials.
The deployment forms part of a broader plan by the three allies to strengthen military cooperation in the Pacific amid growing concerns about China’s military expansion in the region.
In a joint statement, the countries described the move as a “significant milestone” in establishing a shared deterrence force under the AUKUS security agreement.
The pact aims to help Australia acquire a fleet of nuclear-powered submarines while expanding defence and security cooperation among the three nations.
Australian base to host five allied submarines
The submarine will join the planned Submarine Rotational Force-West, which will operate from HMAS Stirling, a naval base in Western Australia.
Under the arrangement, the base is expected to host up to five fast-attack submarines on a rotating basis. Four will come from the United States, while the United Kingdom will provide one.
The initiative will also help Australia develop the skills and infrastructure required to operate and maintain its own nuclear-powered submarines. HMAS Stirling will support allied deployments and submarine maintenance.
Australian Defence Minister Richard Marles described the rotating force as the first “really big milestone” under the AUKUS agreement.
“It’s on track,” Marles told News24, adding that American personnel were already at HMAS Stirling preparing the site.
The submarine arrangement represents a major investment in Australia’s long-term defence capabilities.
Government forecasts estimate that the wider AUKUS submarine programme could cost up to US$235 billion over 30 years.
Although Australia does not permit foreign military bases on its territory, it hosts US Marines in Darwin for training exercises lasting six months each year.
The submarine rotation arrangement will deepen military cooperation between Canberra and Washington while increasing the presence of allied naval forces in the Indo-Pacific.
The AUKUS partnership centres on helping Australia acquire nuclear-powered submarines and strengthening cooperation in defence technology and regional security.
The planned deployment of USS Colorado to Western Australia in late 2027 will be an important step in implementing the agreement, as the three allies seek to strengthen their military coordination in the Pacific.
