>If you believe government has a role in enforcing the NAP, then it's legitimate for the government to enforce isolation measures.

I don't think most libertarians would interpret doing something that has such an indirect pathway to harming someone as aggression. If you're an at-risk group and somebody comes too close/coughs on you, I could see that being perceived as violating the non-aggression principle, but not e.g. two people having drinks at a bar together, which increases the chance of a virus spreading, which increases the chance of you eventually getting it. Especially when trying to stop that indirect violation would be a very direct violation of the rights of the bar owner and patrons to property and free association.

I think you're right about most libertarians. The ones I've known have been vehemently against smoking bans in restaurants, for example, or any action on climate change. That's one reason I've pulled away from the libertarian movement.

However, if we want a society that's not helpless against deadly pandemics, I don't think that means we have to abandon libertarian principles. We just have to apply them in a slightly different way.

I tend to agree, I still have libertarian instincts on a lot of issues, but in situations such as a pandemic where we have a large collective action problem and no time to evolve the sorts of cultural technologies and norms that generally evolve to solve collective action problems, having a government coordinate action is a net benefit.

That said, the libertarian inside me worries a lot about how the surveillance mechanisms we setup to deal with the current pandemic will persist and be repurposed for more nefarious means after the current crisis is over.