If you look at the corona situation in (western) Europe, you will find that 3 countries now have far less infected than the rest. Norway, Finlandand and Iceland. There's also Greece, but for this discussion I'll not include that country.
Now, what's common for these three countries? Well, all countries have very good social security systems, which helps. Also - at least in Norway we trust our government, and therefore tends to follow the rules. Now, there are things to be said about both these issues (which for all I know are already discussed in the P&R forum which I don't visit), but for this particular setting it helps.
However, the same can be said about several other European countries.
There is another comon factor for these countries, which I think is very important: We're all thinly populated. In Norway we're around 14 people per square km. Compare that to for instance the Netherlands with more than 300. This means that in the current situation where now - at least in Norway - most outbreaks are local, they tend to remain local. For instance, few people from my home town, Bergen see any good reason to travel 430 km in order to go to our third biggest city, Trondheim (and fortunately few from Trondheim come to Bergen). We've had local outbreaks in Bergen, which didn't affect Trondheim, and the recent outbreak in Trondheim didn't come here.
I think this is a very important factor, which sadly cannot be ethically implemented in the rest of Europe.
But I wonder: I assume that there are thinly populated states in the US. Are there similar differences over there?
an incarnation of pibbur who observes that down under is even more thinly populated than Norway.
PS. Faroe Islands (to some degree part of Denmark) is also thinly populated and has a low number of infections. DS.