I think you over-estimate the appetite for violence in the general population. The 3%'ers, Proud Boys, some of the Christian Identity and white nationalists would probably show up but I think the vast majority of regular people would simply demand order be restored. Then demand these groups be stomped flat as domestic terrorists. A lot of these guys are inheritors of that anarchist/post-apocalyptic/end times fantasy of the 70's and 80's but won't last when it's shown how much of a minority they are. If that kind of violence was probable, we would have seen it after the 2000 and 2016 elections.what would be perceived as a political coup turning into a violent response.
What it really comes down to is those that get spun up at the thought of political violence are a minority of a minority (hence the 3%er term) and the idea that the 3rd Infantry Division would desert in mass to support them or that a bunch of wannabe's running around in camo could stand up to a veteran military unit is ludicrous.