I domt think there will be a civil war and if so it will be short. A few things that are being overlooked.
1.The current population can not stomach a prolonged war. Look at how many veterans off themselves or have ptsd and are barely functioning. Those are the trained individuals how do you think your instagram addict or netflix Binger would fair. This isn't a population that is used to committing or receiving violence. This is not the middle east, africa or China, all areas whose populations have a history of warfare on their own soil. The majority of the population would lick the boots of whichever force can turn the "internet" back on faster then you can say super bowl
2.Despite having weapons most are not trained to use them and even if they are pinging a metal plate is not the same as shooting flesh and blood. The only ones who would be able to stomach that are vets, military, and trained militia. Most of the gun purchases in the last 6 months are from terrified citizens that probably thought before the current riots "I dont need a gun".
3. Defining the enemy would be difficult. Despite what people claim they will go with the majority. Most of the people protesting are connected through school, friends, and common interests. Same thing can be said with the majority of both the left and the right. Those are great if you are winning a popularity contest but not that reliable when your facing possible starvation, rape , or murder. Once bullets start firing mom and dad will get off their lazy behind and tell Britney to stop messing around with her friends in the street and come home, especially if infrastructure starts getting hit. How do you know whose a Democrat or republican from the outside through a scope?
3. The international community could not allow us to be in chaos for an extended amount of time. Financially we have our hands in alot of pockets and if this country fell alot more would begin to crumble due to our lack of protection, resources, and influence. Even our enemies would need us to get back on our feet just so they can have an enemy to fight against.
I could be wrong about all 3 points but I seriously doubt our population has the stomach and drive to sustain a chaotic guerilla style civil war just because we disagree on trans rights or rather or not we should have a border wall. I hope I'm not wrong.