Your stats don't really tell the full picture. The "death rate per case" that you quote should be relatively similar when comparing countries with similar age demographics and primary health care systems. So the percent of people who die once they catch Covid - should be (ceteris paribus) broadly equal in the US and Australia. Because it is a measure of the 'deadliness' of the disease.
But the big difference, and I mean BIG difference is in the effectiveness of each respective countries pandemic/public health response systems. You can clearly see this in the percent of the people who 'catch Covid' in the first place. Australia and the US have approximately the same testing rate - both currently sitting between 265,000 and 270,000 tests per million people. However, in the US the infection rate is almost 20,000 cases per million people, while in Australia it is just over 1,000 cases per million people. So approx 20 times our infection rate, with similar testing rates!! And based on your stats, you would thus expect the death rate (per million people) to also be approximately 20 times higher in the USA than in Australia. And it appears to be approximately so with 589 per million and 31 per million.
Simply put, you are (statistically speaking) 19-20 times more likely to die from Covid in the USA than you are in Australia, simply based on your country of residency. So why is that?
source:
https://www.worldometers.info/coronavirus/#countries
