Kabul: some good must come of this

We should also reassess our military strategy. The reason that the Afghani army was rolled up so quickly was partly psychological – if the Yanks had deserted them, and defeat was certain, then where was the advantage in doing anything other than suing for personal peace and heading off home.

It was also that they had been designed to be only one component in a much more sophisticated fighting force. This is the same model that our own armed forces operate on. It's essentially the Roman model, where the Empire would provide the legionaries and allies would provide light cavalry, archers, slingers. If you take the legionaries out of the mix, you have nothing left.

In Afghanistan, the Afghan army was doing the legionaries work but supported by intelligence and most crucially air-support, which is where much of the heavy military grunt work occurs in modern warfare.

If the US affection for Australia wouldn't extend to supporting us, then our armed forces would be rolled up just as quickly as the Afghan ones. We need to lift our defence spending, and to justify this we need to be much more questioning of the inevitability of US support.

And, in general, we also need to take off our rose-coloured polaroids and see the world for what it is – an often hostile place where no one owes you a living, and where they are happy to take it away if it suits them.

We don't face a threat from anything like the Taliban. Our threat is larger, more potent, and more insidious. The Chinese are offering us client state status. It's not shootings or beheadings necessarily, but at the very least it is tribute and up from there with varying levels of control.

If this is the beginning of the end of US world power, then we need to calibrate for that. And if, as is more likely, it is a very nasty accident in the long march, then we need to consider how we draw the US into a closer alliance, so that unlike Afghanistan, we aren't seen as disposable.

These are not mutually exclusive aims. Afghanistan reminds us that since 1945 we've experienced a period of incredible peace and that the best way to ensure peace is not just to prepare for war, but to have robust plans with multiple redundancies.