I think that localities, including as large as countries, can be meaningfully compared by the measure of positive rate, toward understanding how the infection can be controlled in one place and yet be so out of control in another.
The strategy of identification by testing and quarantine, contact tracing (and testing) is a sound one. Add to that social distancing, sanitary practices, and yes, face coverings, and we (everybody) have the means to control the infection until more effective treatments, including effective vaccines become available. We WILL have effective treatments like plasma-based and monoclonal antibodies and we WILL have vaccines.
Positive rate is simply the number of positive tests as a percentage of total tests administered. Look here, for this measure in each US state
https://coronavirus.jhu.edu/testing/individual-states/usaHere is the state of Maryland. New cases rose, positive rates increased to well over 10%, they installed NPI, then testing dramatically increased and stayed increased. positive rate dropped to ~5% and new cases to 300-400. They still have a ways to go, but it is under some level of control and a slow and cautious reopening is in progress.
Here is the state of Florida. Clearly it became untethered and they have an unacceptably high positive rate and daily new case rate.
I have a pretty good idea of what happened - lapsing or otherwise insufficient NPI. Whether I am right or not about that is not the most relevant issue. The critical issue is that they are not doing enough testing.
Wherever it is, if the positive rate is high, not enough testing is being done to allow the strategy of identification (by testing) and quarantine, contact tracing (and testing), social distancing, sanitary practices, and yes, face coverings, to be successful. THAT is what we are seeing in the US. The most powerful country in the world (IMO) and we can't master testing four months into the greatest pandemic the country has seen in 100 years.
I don't give a rat's ass that the US has done more testing than anyone else in the world, it is distinctly irrelevant.
In Wyoming, maybe the infections are under control and their testing is sufficient - and you don't see 10% positive rates. In Australia positive rates are less than 1%. Good for them, I am happy for the folks in all of those areas.
It is not that everybody has to do the same amount of testing, it is that if the positive rate in a locale is too high, you need to do MUCH more testing. Period, beginning, middle and end of issue. I ulcerate hearing all the subterfuge and obfuscation around some very simple and basic concepts.
If you do not do enough testing, you can't control the spread. It is not rocket science. The virus is not alive, it is a hunk of crap that does exactly what it does without fail (except for some mutating).
Yet, in the US we tolerate BS at the highest levels that say we should slow down testing or that testing will produce more cases so we shouldn't be concerned about a rise in cases. Or that it is our constitutional right of assembly, so we are supposed to be fine having political rallys in hot spots.
Pure unadulterated bullshit. Bullshit that smells so bad, you would never accept something like that in the EE world, yet it is met with far too much acceptance. Let's just wait for herd immunity and resign ourselves to the idea that everybody will get infected....while the economy and healthcare get flushed down the toilet...and it really doesn't have to be that way.