Similar in what ways? Aus is an island country whose societal composition and Constitutional rights are nothing like ours. I wouldn't say they're very similar at all.
Autrstial probably didn't have community spread of covid until Late Feb. But America had community spread in at least mid Jan--and probably earlier. But Australia locked down essentially when America did. If they can eradicate the disease, that's a huge win, but if they can't they are just delaying what happened in America.
Or is your point just that America is Special and can't be compared to anyone?
The key point here is transmission of an infectious disease, so to get a proper comparison, you need to start with approximately the same probabilities of people infecting one another. That begins with proximity. Comparing the U.S. and Australia doesn't work because of that.
Am I here on HN or in r/worldnews?