I just can't understand how very similar countries who started at similar places ended up with very different ideology. We used to have a White Australia policy AND we only saw indigenous Australians as people in 1967. We also had a government removed for being 'socialist' by the governor-General. And yet, we have medicare, child care subsidies and even the guy who brought in coal to scare the Libs has been talking about renewable energy more. Those same people increased the child care subsidy. But Americans polticians were worried about whether money only be spent on new roads, not fix up the old ones that are falling apart. Because that makes sense
I'd say it's down to the following:
-Australia and many parlimentary democracies do, IMO, a better job of representation than the US. The US has two major parties that have to encompass everything from the center to the fringe, and it's gotten worse since at least the 1990s. Places like Oz, on the other hand, have a more sensible centre (ALP vs. LNP), and various other parties people can vote for if they want something else, plus, preferential voting. So I guess in theory, we're in the position to have stuff like Medicare steadily implemented (proposed by the left), and then maintained (by the right). This isn't even an oddity, the Tories grudgingly maintain the NHS after all in the UK for instance.
-Fair to say that the red scare affected the US more than us, so what's "socialism" to a lot of people in the US would be considered centre-left here.
-I guess there's also the cultural divergences that go back to both countries. Both start as colonies of the British Empire, only the US breaks off to do its own thing, while Oz still has the queen as its head of state and the union jack on its flag, and there isn't much appetite for republicanism here. That doesn't explain everything and everything, but, well, pivoting back to the first point, I'm glad we have the system of government that we do, because watching the US descend into hyper-partisanship over the last half decade has been both amusing and terrifying.
Edit: Also, ScoMo and renewable energy...too little, too late. God's sake, I've actually defend ScoMo's handling of Covid here (even if I have to have an LNP prime minister, I'd go with Turnbull), but he and much of the Liberals are still dragging their feet on renewables. But then, that's the COALition for you.