Australian Defence Force

The Australian Defence Force (ADF) is the military organisation responsible for the defence of Australia and its national interests. It consists of three services: the Royal Australian Navy (RAN), the Australian Army and the Royal Australian Air Force (RAAF). The ADF has a strength of just over 90,000 personnel and is supported by the Department of Defence alongside other civilian entities also members of the Australian Defence Organisation.

During the first decades of the 20th century, the Australian Government established the armed services as separate organisations, with each service having an independent chain of command. In 1976, the government made a strategic change and established the ADF to place the services under a single headquarters. Over time, the degree of integration has increased, and tri-service headquarters, logistics, and training institutions have supplanted many single-service establishments. The ADF has been deployed around the world in combat, peacekeeping and disaster-relief missions.

The ADF is technologically sophisticated but relatively small for its landmass. The ADF has 57,346 full-time active-duty personnel and 32,049 active reservists as of 30 June 2023^[update] making it the largest military in Oceania, although it is smaller than most Asian military forces. The ADF is supported by a significant budget by worldwide standards and is well equipped and trained, with defence spending at 2.02% of GDP (as of 2024/25).

By 1870, each of the then Australian colonies maintained their own military forces. On 1 January 1901, the colonies federated into a new nation and on 1 March 1901, these colonial forces were amalgamated to establish the Australian Army and Commonwealth Naval Forces. In 1911, the government established the Royal Australian Navy, which absorbed the Commonwealth Naval Force. The Army established the Australian Flying Corps in 1912 which was separated to form the Royal Australian Air Force in 1921. The services were not linked by a single chain of command, as they each reported to their own separate Minister and had separate administrative arrangements. The three services saw action around the world during World War I and World War II, and took part in conflicts in Asia during the Cold War.

The importance of joint warfare was made clear to the Australian military during World War II when Australian naval, ground and air units frequently served as part of single commands. Following the war, several senior officers lobbied for the appointment of a commander-in-chief of the three services. The government rejected this proposal and the three services remained fully independent. The absence of a central authority resulted in poor coordination between the services, with each service organising and operating under different military doctrine.

The need for an integrated command structure received more emphasis due to inefficient arrangements during the Vietnam War which at times hindered the military's efforts. In 1973, the Secretary of the Department of Defence, Arthur Tange, submitted a report to the Government that recommended the unification of the separate departments supporting each service under a single Department of Defence, and the creation of the position of Chief of the Defence Force Staff. The government accepted these recommendations, and the Australian Defence Force was established on 9 February 1976.

Until the 1970s, Australia's military strategy centred on the concept of "forward defence", in which the role of the Australian military was to co-operate with allied forces to counter threats in Australia's region. In 1969, when the United States began the Guam Doctrine and the British withdrew east of Suez, Australia developed a defence policy which emphasised self-reliance and the defence of continental Australia. This was known as the Defence of Australia Policy. Under this policy, the focus of Australian defence planning was to protect Australia's northern maritime approaches (the Air-Sea Gap) against enemy attack. In line with this goal, the ADF was restructured to increase its ability to strike at enemy forces from Australian bases and to counter raids on continental Australia. The ADF achieved this by increasing the capabilities of the RAN and RAAF and relocating regular Army units to northern Australia.

At this time, the ADF had no military units on operational deployment outside Australia. In 1987, the ADF made its first operational deployment as part of Operation Morris Dance, in which several warships and a rifle company deployed to the waters off Fiji in response to the 1987 Fijian coups d'état. While broadly successful, this deployment highlighted the need for the ADF to improve its capability to rapidly respond to unforeseen events.