There will not be a day where someone says “we declare civil war”
Things will just escalate and escalate until we find we are in one.
I think you might not quite grasp the situation here.
WE THE PEOPLE will not declare a civil war.
Congress and the White house probably will do it themselves.
That kicks in a whole bunch of of nasty things, Congress declaring war bypasses the War Powers Act for one, the declaration automatically voids the Posse Comitatus Act, with all that implies.
They have the F-15s and nuclear weapons.
They have already threatened to use them.
What's that threat assessment formula?
An enemy's ability to do battle X their willingness to use that ability, or something like that.
Their calculus might be: "If we nuke the whitest, reddest city in the reddest state everyone else will snap into line.
It's a small price to pay for saving the rest of the country from the evils of Trumpism!, and communists have never been shy about making such sacrifices. Ask any Ukrainian, Tienanmen square survivor, or Cambodian...