I agree with the premise that there is an insufficiently mature dialog, and engagement across the political spectrum.
But there's been, provably more dismissiveness and ensuing divisiveness within the conservative movement, which is where "Republicans eat their own" came frome. The explicit targeting by far right conservatives to destroy moderate Republicans in elections is not something that is at all common in the Democratic party. It was refined to great success by the Tea Party movement.
Smug liberalism is not at all the same kind of nefarious strategy the far right has used. Smug liberalism is a naive position that if only conservatives had the facts, they'd become liberals/progressives/Democrats or at the very least revert back to being moderate Republicans. It isn't intended to piss people off, even though that has been the outcome.
The political landscape is sufficiently damaged now that there is likely a significant and intractable minority who believe in a different reality where liberals are out to get them; that corporations and billionaires are out to screw them by hiring "illegals" (except for Trump's hand selected billionaires, they're the good ones); and that import tariffs are paid by foreigners. Damaged by the likes of Newsmax, Infowars, and Breitbart (previously run by now Chief Strategist and Senior Counselor to the U.S. president) are all far right sites trafficking in varying degrees of mistruth. These are not policy disputes, these are disputes over facts.
I do not think there is any fixable relationship when two sides are disagreeing on world view: how the world works, how it should work. They are mutually incompatible right now, and the thing to be negotiating is the outcome of losing arguments, which hopefully remain non-violent. The language of name calling and violence is destabilizing whether it is a one on one relationship, or directed at countries. The president is openly combative with everyone who disagrees with him. It'll be deeply fascinating to see how things go when those disagreements happen with people he's hand selected - which is why I think it's important senators support pretty much all of his cabinet selections, at least all of them are completely sane.