In the 3 pronged attack against Trump; impeachment, Special counsel and the 25th amendment, I imagine the first two coinciding and the 25th being least likely to succeed.

It is pure guesswork if Trump and Bannon will call on armed right wing militias to further their cause after being deposed with domestic terrorism aimed at the left. We can be certain his cause will continue on twitter no matter what. Unless sedition is enough to ban twitter accounts.

Calling such behavior a civil war is unhelpful but possible.