We aren't talking about a civil war though, we are talking about a civil uprising. Trump didn't take the government by force or strongarm politicians into compliance, they mostly went along with all this bullshit too. People already had the view that federal politicians as a whole were corrupt and self-serving and have been failing to effectively govern and legislate in the country's favor for decades. I also doubt any or enough of them would be willing to take up arms themselves and become a factional leader. Nobody is going to rally behind Kamala or some geriatric or the democratic party even if they were willing to try.

And in an insurgency type situation private arms/small arms are extremely effective, if costly with lives. The US failing to subdue multiple countries long term despite having a tiny fraction the amount of small arms, veterans, or people directly involved in US logistics operations, is all the proof we need. Nobody wants that, it would be horrendous and bloody, but tanks and planes don't run off mere hopes and dreams and the US citizenry is more heavily armed by multiple factors than any other country or people in history.