As I wrote in the last sentence you quoted, I'm not advocating this, I am simply asking the question to see whether or NOT there would be a benefit to studying the various responses. We are all commenting on how other countries handled it differently, and I am assuming that the medical community is learning from these different responses. I'm asking if lessons could be learned from how different states in the US are responding. I think the answer is yes, because people are discussing, criticising and applauding the various responses from some states over others.
You are also assuming that there is free travel across state borders in the US. It is not clear to me that that is the case, or that it always will be, even if it is now. There are examples of states, towns, and other local communities, that are advocating for a prohibition of travel into their communities. This will increase if the the situation continues to get worse. Most, but not all, trains, airplanes and buses seem to be shut down. There was a story yesterday about seven guys being fined in CA by the local authorities of one town from crossing into their town from another town to buy liquor. Each guy was fined $1,000. This sounds to me as though local travel is being restricted or very soon will be, on some level.
Are you also advocating for Brussels to shut down all of the EU? I don't hear such calls, from anyone. Why not? Isn't the EU more analogous to the US? Why isn't there widespread testing in the EU, why are there different responses being allowed by different countries? Why are some borders closed and others not? Why the inconsistent approach to the pandemic? The EU was supposed to be the new ideal. Why is no one asking these questions?
The US keeps getting compared to South Korea, or Italy, or Sweden, all smaller, more homogenous cultures and populations with different sets of laws and behavior patterns. In my view, the US should more rightly be compared to the EU as a whole.
I am not proposing answers because I lack the qualifications and am not in a leadership position. (I already hear many snickering), but I am just making observations and asking questions to further the discussion and learn something.