It's an interesting hypothesis that more guns in the hands of civilians would have resulted in less bloody conflict (as opposed to military escalation in light of armed resistance), but I don't know how one proves it. What's the control group?

I don't think the claim has ever been that it would result in less bloody conflict. On the contrary, likely more bloody.

I think the claim is simply that it can potentially change the outcome.

And before anyone disagrees, how many soldiers died in Iraq & Afghanistan at the hands of insurgencies?

Plenty, until the US pivoted to drone-launched missiles.

Have fun launching missiles at American cities and insurgents embedded in civilian targets. Even shooting missiles at the desert kill enough innocent bystanders to radicalize the enemy, now imagine doing that in Miami and Houston.

I have imagined it, and it's horrifying. But not guaranteed to radicalize people outside the immediate effected area against the ones pulling the trigger.

Philadelphia bombed a city block to flush out an entrenched armed group in the '80s, and life went on (for everyone who didn't have their home burned down). Don't underestimate the American capacity to believe something was done because it was necessary. It's the only country to have ever deployed nuclear weapons. Twice.

The MOVE incident was gross incompetence that spiraled out of control. If you have one of those every month, in every city, on purpose, the country is going to completely break down.

Heuristics. What are the 2 longest-standing governments in the world? US and SUI

What are the 2 most-armed civil societies in the world? US and SUI

Then you have the other end of the spectrum: is regulation of private gun ownership predict government turning on its citizens? No.

Is regulation of private gun ownership a prerequisite for authoritarian govts to turn on citizens? Yes