March 1, 1901 marked the establishment of Australia’s Commonwealth military and naval forces, the foundation of today’s Royal Australian Navy and Australian Army. The sea service’s initial title was "Commonwealth Naval Forces"; a decade later King George V granted the title "Royal Australian Navy".
When the new fleet steamed through Sydney Heads in October 1913, Australians lined the harbour to witness a visible expression of sovereignty that had long rested with Britain.
From the outset, some of Australia’s strategic thinkers understood a simple truth: the nation’s prosperity and security would rest on control of its surrounding seas. As an island continent dependent on maritime trade, Australia’s economic lifelines have always run across the sea.
In the early decades of federation, that burden was largely carried by the Royal Navy. The fall of Singapore in 1942 exposed the limits of that assumption.
The Royal Navy was not coming. Australia turned to the US Navy instead. The underlying reality did not change. Maritime power sits at the centre of Australia’s security.
One hundred and twenty-five years after federation, the RAN faces a demanding decade as it seeks to renew its surface fleet and submarine force. The maritime domain is more contested than at any time since World War II. Attacks on maritime infrastructure and merchant shipping, rapid naval build-ups, and the erosion of restraints on the use of force all point to intensifying strategic competition at sea.
Yet it is across this domain that Australia’s critical lifelines travel: fuel, fertiliser, chemicals, pharmaceuticals and other essentials on which both the economy and the ability to fight depend.
For decades, distance has been described as Australia’s strategic advantage, the sea cast as a moat. But Australia’s early strategists recognised a harder truth that remains valid today. The sea is also our vulnerability.
Access to secure seaborne supply is not peripheral to national security. It is central to it. Yet Australia’s naval force structure has not always kept pace with that reality.
As technology evolves, the RAN will be required to shoulder a broader set of responsibilities than it did in either of the world wars.
The growing willingness of states to resort to military force and the resulting contestation of the maritime domain therefore represents Australia’s central military challenge.
That reality was underscored in 2025 by the arrival of two separate Chinese naval task groups operating near Australia. It marked a significant shift: a regional power demonstrating the capacity to operate sustained naval forces in Australia’s approaches and, if required, put maritime lifelines at risk.
Australia faces its most demanding strategic environment since World War II, and the RAN arguably confronts its most consequential period of reform. It must operate in an increasingly contested maritime domain while simultaneously recapitalising its fleet and introducing new capabilities.
As technology evolves and the methods of warfare adapt, the RAN will be required to shoulder a broader set of responsibilities than it did in either of the world wars, while adapting to long range strike, uncrewed systems, intensified undersea competition, cyber operations and contestation in space.
All of this is unfolding at a time when Australia is a fundamentally different country—demographically, politically and industrially—from the one that fought the world wars. The default reliance first on the Royal Navy and then on the US Navy no longer sits comfortably with contemporary expectations of sovereignty and responsibility.
The alliance with the United States remains central to Australia’s security, but the notion that Washington would assume primary responsibility for Australia’s defence, as it effectively did in 1942, is unlikely to be acceptable to a modern Australia.
After decades of delayed decisions, Australia now fields one of its smallest and oldest surface combatant fleets since WWII, alongside an ageing Collins-class submarine force and limited surge capacity in the Naval Reserve.
The choices made in this decade will determine whether the navy can meet the demands placed upon it.
Plans are in place to arrest that decline through the Hunter-class frigates, the acquisition of Japanese-designed Mogami-class frigates, and the transition to nuclear-powered submarines under AUKUS. But these capabilities will not arrive until the 2030s, and each brings its own workforce, industrial and operational challenges for the RAN.
Amid this period of change and challenge, the RAN must also reconnect with the Australian public, as it did in 1913 when the first fleet unit, a formation led by the battle cruiser HMAS Australia, sailed through Sydney Heads.
Naval power has always required public understanding and political backing. Acquiring the first fleet unit was not inevitable. It was argued for forcefully in the national press by then-Captain William Creswell, the architect of Australia’s naval foundations.
That same clarity of purpose will be required again to bring the public along on AUKUS and continuous naval shipbuilding. The RAN must be present in the national debate.
The 125th anniversary of the RAN is more than commemoration; it is a reminder that maritime security remains central to Australia’s national survival, and that the choices made in this decade will determine whether the RAN can meet the demands placed upon it.
One hundred and twenty-five years on, the RAN enters a decisive decade. It demands resolve from the navy and the nation it serves.
Article reprinted with permission from the Australian Strategic Policy Institute's analysis and commentary site The Strategist.