Defence of Australia Policy

The Defence of Australia Policy was Australia's dominant defence policy between 1972 and 1997. The policy was focused on the defence of continental Australia against external attack. The Australian Defence Force was tailored to defending Australia rather than developing capabilities to operate outside Australian territory.

The Defence of Australia (DOA) policy was adopted after the previous policy of "forward defence" was discredited in the public eye by Australia's involvement in the Vietnam War. The policy was developed during the 1970s and early 1980s before it was formalised in the 1986 Dibb Report and the 1987 and 1994 Defence White Papers.

The focus of Australian defence planning was to protect Australia's northern maritime approaches (the "air-sea gap") against enemy attack. The ADF was restructured to increase its ability to strike at enemy forces from Australian bases, by increasing the size and capabilities of the Royal Australian Air Force and Royal Australian Navy, at the expense of the Army and the forces used to project Australian power overseas (such as Australia's aircraft carrier, HMAS Melbourne, which was retired without replacement).

Specific force structure changes introduced under the DOA policy included:

Nevertheless, the adoption of the DOA policy did not involve Australia adopting a policy of neutrality or completely disbanding its ability to deploy forces overseas. During the DOA era, Australia maintained its alliances with the United States and New Zealand and sought to develop stronger defence relationships with South East Asian countries. In addition, the ADF maintained a sizeable force of transport aircraft and amphibious ships and an infantry brigade capable of rapidly deploying overseas (the 3rd Brigade). Furthermore, Australian forces continued to be deployed overseas for exercises and peace keeping operations, and a small Australian military base was permanently maintained at Butterworth in Malaysia.

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