The principal objective of defence policy is national security. National security is, of course, concerned with far more than the state of the armed forces. The level of military power is dependent on a host of complexities including national assessments about the external environment, the scope for conflict with potential adversaries and the help that might be expected from allies.

On first inspection the five years from 1976 to 1980 appear to be a period of little moment in the history of Australian defence policy. No Australian servicemen were engaged in combat, no direct threat to Australia emerged even of a minor nature, no far-reaching organisational changes in the armed services or the Department of Defence took place, and relatively little new equipment found its way into the hands of the Defence Force. Moreover, the Liberal-National Country Party government retained office throughout the period, defence policy being a minor issue in the elections of 1977 and 1980, and Mr D.J. Killen remained Minister for Defence. Nor, despite early projections, did defence spending increase significantly between 1976 and 1980, fluctuating between 2.6 per cent and 2.8 per cent of Gross Domestic Product.

Perhaps the most important question to be examined in a review of Australian defence policy during 1971–75 is how much fundamental change occurred. There is a strong prima facie case for holding that the period was the most consequential five years for Australian defence policy since the Second World War. The change of governing parties in late 1972 marked the end of an era when foreign and defence policy issues played a significant part in determining the outcome of the seven successive general elections won by the Liberal and Country Parties between 1951 and 1966. Even in 1969, Australian involvement in Vietnam was not sufficiently unpopular to unseat the Gorton Government which was troubled on many fronts. Because defence was an important electoral issue throughout the 23 years of Liberal-Country Party rule, it seemed only reasonable to expect marked changes in this area following their loss of office.

In retrospect, the dominant feature of the period 1966–70 was the virtual withdrawal of one of Australia’s great-power protectors, Britain, coupled with the new uncertainty over the long-term role of the other, the United States. By 1970 it was accepted that Australia faced a novel strategic situation, though there was no agreement on the appropriate response, nor had the debate on the implications of the new situation been very searching.