Australia is one of the wealthiest countries in the world, ranked in the top 10 in gross domestic product per capita. It is one of the most isolated major countries in the world; it occupies an entire united continent, is difficult to invade and rarely is threatened. Normally, we would not expect a relatively well-off and isolated country to have been involved in many wars. This has not been the case for Australia and, more interesting, it has persistently not been the case, even under a variety of governments. Ideology does not explain the phenomenon in this instance.
Since 1900, Australia has engaged in several wars and other military or security interventions (including the Boer War, World War I, World War II and the wars in Korea, Vietnam, Afghanistan and Iraq) lasting about 40 years total. Put another way, Australia has been at war for more than one-third of the time since the Commonwealth of Australia was established in 1901. In only one of these wars, World War II, was its national security directly threatened, and even then a great deal of its fighting was done in places such as Greece and North Africa rather than in direct defense of Australia. This leaves us to wonder why a country as wealthy and seemingly secure as Australia would have participated in so many conflicts.
Importance of Sea-Lanes
To understand Australia, we must begin by noting that its isolation does not necessarily make it secure. Exports, particularly of primary commodities, have been essential to Australia. From wool exported to Britain in 1901 to iron ore exported to China today, Australia has had to export commodities to finance the import of industrial products and services in excess of what its population could produce for itself. Without this trade, Australia could not have sustained its economic development and reached the extraordinarily high standard of living that it has.
This leads to Australia's strategic problem. In order to sustain its economy it must trade, and given its location, its trade must go by sea. Australia is not in a position, by itself, to guarantee the security of its sea-lanes, due to its population size and geographic location. Australia therefore encounters two obstacles. First, it must remain competitive in world markets for its exports. Second, it must guarantee that its goods will reach those markets. If its sea-lanes are cut or disrupted, the foundations of Australia's economy are at risk.
Think of Australia as a creature whose primary circulatory system is outside of its body. Such a creature would be extraordinarily vulnerable and would have to develop unique defense mechanisms. This challenge has guided Australian strategy.
First, Australia must be aligned with -- or at least not hostile to -- the leading global maritime power. In the first part of Australia's history, this was Britain. More recently, it has been the United States. Australia's dependence on maritime trade means that it can never simply oppose countries that control or guarantee the sea-lanes upon which it depends; Australia cannot afford to give the global maritime power any reason to interfere with its access to sea-lanes.