> I’m not sure the federal government has the plenary power to enforce such things in the United States.

I am certain it hasn’t. But the same reasoning applies for state governments. Having public health decisions taken at the county level is sheer madness.

> The lockdowns, even as implemented, extracted an enormous toll on small businesses and mental health.

This is entirely true, and I hope this will make people and governments take health issues and depression more seriously. Now, we don’t have an alternative earth to experiment, but whether one strict lockdown for 6 months followed by progressive reopening is better or worse for people and the economy compared to a succession of waves and partial lockdowns with no end in sight should certainly be discussed.

This is even more skewed in countries that do not have a proper safety net and where people have the choice between going to work ill or not having a job.

I think it's more of a cultural difference rather than government one. Korea and Taiwan are democracies and managed to control the pandemic as well. The US government has the authority to declare martial law, but doing so would completely undermine people's faith in the government.

There is certainly a cultural element, but it is literally a legal difference as well. The federal government in the US does not have the same broad powers as the federal government in Korea. Remember the US is a collection of states that consented to let the feds take on certain powers while retaining many, whereas South Korea is “just” South Korea. Provincial autonomy in SK is not anything like the “state’s rights” issue in the US.