I think back to when the D party had moderates - Adlai Stevenson, Hubert Humphrey, and of course JFK. I was a youngster then, but were I to meet with any of these men as an adult, I bet we could have a civil discussion on various issues - we'd find some common ground, and agree to disagree on other matters. Afterwards, we'd shake hands, wish each other well, and part amicably.
I don't think civil discourse is possible with some (many?) of today's democrats. Within 5 minutes they'd be cursing and insulting me, telling me I had NO right to hold the positions I do, that I was sexist, nativist, racist, and every other -ist they could think of. Some might even think they could smack me without receiving a like response.
The lunatics ARE running the asylum.