In terms of screening people returning from abroad to the US, if we had immediately established a regime of either testing or mandatory self-quarantine, that would have greatly reduced the rate of transmission.

Doing widespread spot testing across the country would've identified the communities where the virus was extant. From there we would've known where to focus the brunt of universal testing, tracking and quarantining.

Just the fact that we are still fiddling with estimates of what percentage of CV infected people are asymptomatic is a travesty. We should have long ago conducted enough statistical sampling to have a very clear picture what was happening in our communities.