Re: The Question of Australia
DWill, I think it is abundantly clear that the USA is not living sustainably, and nor is Australia. We have passed peak phosphorus and peak oil, and are pushing the planet towards a runaway greenhouse effect through accelerating CO2 emissions. We need a systemic shift of energy supply and resources to avoid collapse. I think such change is possible through new technology, but without such change we are headed for the four horsemen of the apocalypse - famine, plague, war and death. Things that are not sustainable stop.
Australia now feeds 60 million people including exports. But much of this comes from mining the land, through use of fossil water and fossil fuel. Systems based on finite fossil resources are by definition unsustainable. Diamond is right that Australia is particularly crazy when it comes to wrecking fragile ecosystems. We have the highest rate of mammal extinction on the planet. You might be interested also to see the book by Tim Flannery, The Future Eaters, which also takes Easter Island as a planetary parable. Flannery explains that when the Maori in New Zealand ran out of megafauna, they started eating each other.
I agree with Diamond on the need to shift the economy from the colonial plunder model, but the national identity question is harder as I think that British heritage is valuable (although plunder is a great British pastime going back to Drake and other pirates). I have previously expressed my views on the potential to develop new technology for sustainable agriculture and energy, and can repeat those if anyone wants to hear them.