>>20001An invasion of Australia would be a logistical nightmare, even with our tiny military, passive/weak population, lack of chemical weapons/nukes/ICBMs, etc.
China is one of the few countries with the military capabilities & population which could pull it off at tremendous cost, but what China has going for them is that they don't actually have to invade us. We're an Island state far separated from our allies with neither significant light or heavy industrial capabilities - unable to produce even a significant portion of consumer goods necessary for a fairly spartan existence, and certainly incapable of autarky in military production. What's worse is that we hardly produce any oil at all, which even if we did refine here, wouldn't cover military/government needs let alone civilian (ie, agriculture).
All China would have to do is park a small portion of its massive navy on our coasts and they could effectively starve us out within months. Australia has no strategic fuel reserves, so not long after 20-30 days even the military/government run out of fuel, power stations start going off, transport between major cities/rural areas becomes almost impossible and agriculture falls apart. Even before the tractors and combine harvesters, etc stop running and the food rots in the fields, Our supermarkets - which depend on just in time logistics, run out of food and basic goods within a week. With limited fuel and no transportation inner-city let alone between urban hubs, cities begin starving as soon as people run out of food in their pantries. The govt, deprived of fuel, is going to be in no position to begin feeding people. Once the power goes off, water pumping goes off, which means most of the country is without water, and now there is no means of transporting it.
All it would take is 6 months of the blockade and the death toll would be in the many millions. Under similar conditions, the US estimates that 2/3 of their population would die off in a year - we'd likely see similar casualties here. This is assuming that they don't start lopping cruise missiles at us from their ships either - a real possibility for which we have absolutely no defense.
It would only take a portion of the Chinese navy. mostly just submarines for a few months to achieve to this. Anybody who thinks the US would intervene to save Australia - risking San Francisco, Los Angeles, and Seattle in the process is nuts. The US navy will be spread thin and likely will take heavy losses, in the beginning, weeks/month of the war, losses which they are incapable of replacing as they've lost most of their shipbuilding capabilities having long since outsourced them to south Korea and China.
When I call this "suicide" it's not any kind of an understatement. It'll be suicide of unprecedented, apocalyptic proportions.