True. But if we don't have the stomach to wage total war against the people of Afghanistan, why do you think we'd have the stomach to wage total war against (a portion of) the people of the US?

I'm contesting the statement If anything the war in Afghanistan has proven that technology is no match for resilience and grit.

It's not really technology holding us back, in either situation. Fear the day technology is good enough that the few can act without the restraint of civilization.

It didn't work out that way when the Nazi's invaded Russia.

https://en.wikipedia.org/wiki/Soviet_partisans

>The partisans made significant contributions to the war by frustrating German plans to exploit occupied Soviet territories economically, gave considerable help to the Soviet Army by conducting systematic strikes against Germany's rear communication network, disseminated political work among the local population by publishing newspapers and leaflets, and succeeded in creating and maintaining a feeling of insecurity among German forces.[1]

Not even close to the same asymmetry in capabilities.

I suppose civil wars and internal conflicts have a habit of being much more vicious, so this is something to consider.

The point is that nation building exercises don't demonstrate anything about the capabilities of a modern military. If you are trying to win hearts and minds, you are behaving very differently than if you seek to kill or cow.

Personally, I'd expect the main skirmishes in a US civil war to be factions of the military fighting against each other.