Dissolve the constitution and call for a new constitutional convention?

Sure. The civil war that would inevitably result from that almost certainly wouldn't result in 500,000 dead due to modern medicine. All of the people who died in the first civil war from things that we consider simple to treat now (like infections) would survive.

But I have a feeling that's not what you meant.

Maybe. Maybe. Or maybe that triggers the civil war.

Look, it's possible. It could even be what we need. But for it to work, we'd need wisdom and honest compromise, not sound-bite driven trench-warfare politics. Under current conditions, I see a low probability that it would work.

Or perhaps mandatory civil service?

https://foreignpolicy.com/2021/10/31/us-democracy-mandatory-...

In a country where a sizable minority feel that simply wearing masks during a pandemic is an unconscionable infringement of personal liberty?

That same country still has a mandatory selective service for the military.

No it doesn't. It has a purely voluntary military. (People still have to register for selective service, but there hasn't been a draft in decades.)