The United States and Australia are moving to transform HMAS Stirling, the Royal Australian Navy base on Western Australia’s coast, into a forward hub for allied nuclear submarines. Washington plans to rotate up to four U.S. submarines through Stirling over the next few years, with the first expected as early as 2027, giving American undersea forces a berth closer to potential flashpoints while avoiding some vulnerabilities of Guam.
Allied commanders describe Stirling as a strategic compromise: near enough to the South China Sea and Taiwan to shorten maintenance and turnaround times, yet distant from the range of some mainland missiles that could threaten bases further east. Recent visits by Virginia-class boats, including a month-long stop by USS Vermont, and joint maintenance work there illustrate the practical benefits of an additional forward facility and a capacity to conduct dozens of maintenance tasks away from U.S. yards.
Canberra is underwriting much of the infrastructure upgrade. Australia has committed roughly $5.6 billion to Stirling for training facilities, housing, dock modifications, radioactive-waste handling and power upgrades, while a separate $8.4 billion program at Henderson on the mainland will build a full maintenance and shipbuilding precinct, including dry docks for heavier repairs.
Officials frame deployments as rotational rather than permanent, reflecting Australian legal and political limits on foreign bases. Still, preparations and staffing plans — an estimated 1,200 U.S. and British personnel are expected to move to the region — suggest a sustained allied presence. Britain has also signaled intent to operate submarines from Stirling under AUKUS arrangements, and Australia is contracted to acquire Virginia-class nuclear boats from the United States in the 2030s.
The military logic is straightforward: dispersal and redundancy reduce single-point vulnerabilities. Guam and Pearl Harbor have long been primary maintenance hubs for U.S. submarine forces, but their concentration makes them attractive targets in a high-intensity conflict. A functional shore-based maintenance facility in Western Australia would give U.S. submarines another proximate option to return to service faster and sustain operations in a contested environment.
The initiative is not without controversy. Local residents and some politicians express anxiety about radioactive waste, pressure on housing markets and the risk that increased submarine activity could make the southwest coast of Australia a target. Political actors on the left, including the Greens, have been vocal in opposing the expansion, framing it as an unwelcome militarisation of a previously quiet coastline.
For Beijing, Stirling will be viewed through the prism of containment. The base’s expansion tightens the web of allied logistics and interoperability around potential Taiwan contingencies, and will likely prompt Chinese planners to adjust targeting priorities, force posture and diplomatic responses. That dynamic raises a strategic tension: greater allied integration enhances deterrence but also risks escalating arms competition and hardening regional fault lines.
Key near-term variables to watch are the arrival timeline for the first rotating submarines, the operational tempo of maintenance work at Stirling and Henderson, domestic political pushback in Australia, and Beijing’s military and diplomatic responses. Together these factors will determine whether Stirling becomes a decisive node in allied deterrence, a flashpoint for escalation, or a long-term logistics asset that reshapes Indo-Pacific naval operations.