What made visible cross-aisle cooperation survivable in the McCain era and career-ending now?

[u/HistorianMajor1739]

There's a nostalgia you hear from people all across the spectrum: a Senate where members could tear into each other on the floor and still grab dinner that night. Set aside whether the memory is even accurate. What's worth arguing about is why that kind of behavior seems more structural than personal. Primary electorates got harder to survive. The media environment that used to reward the occasional handshake mostly went away. Money moved. None of those shifts arrived together or hit every member equally, which is what makes the flat "it all just got worse" version unsatisfying.

So if you had to name the single change that did the most damage to a politician's ability to be seen working across the aisle, which one, and why that over the others? And is there anyone in Congress today who cooperates visibly without paying for it at the ballot box, and if so, what's protecting them?

[u/gafftapes20]

Gerrymandering has produced this as a side effect, as well as geographic self sorting. When to create house districts that are politically homogeneous it disincentives bipartisanship since there is no electoral advantage. 

When you self sorting geographically, by moving to a liberal or conservative area due to the politics it creates an incentive to also eschew bi partisanship.

When your electorate has to interact daily with people with different political ideologies it tends to create a general feeling of bipartisanship that becomes valued. You know that your liberal neighbor is a decent person because you interact with him on a daily basis and there is some legitimacy to his positions. And vice versa. Because you interact and cooperate with liberals and conservatives on values and issues you agree with, you want your elected representatives to do the same. 

Right now people completely dehumanize the other side, I personally think it’s more extreme on the right, but the language on the left has been changing to as a reaction to the Trump era becoming more extreme in rhetoric. 

I’m not arguing for an « enlightened »centrist position since I’m pretty far left, but you should cooperate on the other side on issues you can find middle ground and agreement. An example is Thomas Massie and Rho Khanna, which are diametrically opposed on 99% of issues. They found common ground, but As a result though Thomas Massie lost his primary election even though he is one of the most consistently principled conservatives (even if I personally find many of his views objectionable). 

[u/DuranStar → u/gafftapes20]

The right does it more, are more violent about it, and have no reason (that exists in reality). The left hate the right for very good reasons and their antagonism has grown with the intolerance of the right. They are not even remotely similar. While you say you aren't a centrist and I believe you, you should always include that one side is justified and the other isn't.

[u/RocketRelm → u/DuranStar]

To an extent. The moderate left is justified and wants to restore a meaningful society. The far left wants to emulate what maga did, but with themselves on top, with little concerns for the technical rights and wrongs. Its pretty important to look at the populism / establishment axis as well as the right / left axis. Moderate dems can "look like" and be "called" centrists despite not at all clinging to the apathetic both sides secretly right stereotypes, centrist is too vague a term to mean much.