re: What possible route to civility is left at this point?

There is none. The left has no interest in having any sort of conversation.

They are unhinged and completely emotional at this point.

You can't reason with unreasonable people.

I don't think moderates quite understand how dangerous and violent these people are (and are becoming).

The left has had to hide their contempt for America and traditional American values for a long time. Their masks are coming off.