When GWB called for an "coalition of the willing" to invade Iraq, in Australia, we all knew we would be part of it and not because it was a just and honourable endeavour. We knew because, when George Bush sneezes John Howard runs for a hankerchief. John will claim he was simply honouring the ANZUS alliance that has been in place for many years now and probably he was but what value is that alliance? Does it actually mean anything? If it came to the crunch and Australia was invaded by Indonesia, who aferall are the most likely protagonists if only because of their proximity, would the USA come to our aid?

Ashley Leeds, associate professor of political science at Rice University, thinks that probably they will. In a study of alliances entered into between 1816 and 1944 whe found that 75% of the time that they were honoured. The circumstances in which they are broken are typically when there is a massive change of power within a country, such as an overthrow of a regime. Additionally, non-democratic countries major powers that suffer lower costs from reneging are more likely to break alliances.

In conclusion she says

Leaders should assume that under most conditions, allies will fulfill their promises. This means that engaging a state in war when allies have promised to intervene is a proposition that entails a significant risk of war expansion. It also means that the deterrent and compellent properties of alliances should be taken quite seriously

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