-The so-called Us vs. Them divide, where 'Us' is supposedly the Left and 'Them' is the Right. It should be reminded - not for the first time, and certainly not for the last time - that there's more to the American political spectrum than the overwhelmingly American Quillette audience may think. For the rest of the Western world and many non-Western democracies, Democrats are in fact right-wing; and the views of Republicans on many social issues would pass as either far-right or so outlandish as to be hard to make sense of. From there, it makes sense that if you are left-wing (in the 'rest of the world' sense, not the Quillette one), you are going to perceive much of the American 'left' as part of the right. It's not that there are 'tribes' - it's the fact that actual left-wing beliefs are fringe in America. I find it ludicrous when huge tech corporations that operate in at-will employment states, dodge taxes and labor regulations are routinely accused of being 'too leftist'.
-'Our brains evolved for tribal warfare'. I know this is Quillette, but come on.
-The whole article permeates with a rhetoric whereby one's point of view is placed above the fray and draws facile analogies with history (people refusing to associate with right-wingers in college campus vs. e.g. people refusing to eat unclean animals for religious reasons). It follows that line of reasoning where the speaker is unbiased, logically-minded and in full possession of the facts whereas the opponent is emotionally driven, cannot comprehend any argument and lashes out like an animal. I don't believe this tactic is so far removed from the so called 'ad hominem' attacks the author mentions in the article.
Lastly, and this is more a general point on 'discriminating the writer': people attack each other for their opinions all the time, and have been doing it for millennia. Pretty much all philosophers, scientists and other such people that we typically hold to be great thinkers were not above attempts to discredit, debase or otherwise humiliate their intellectual opponents or rivals. Voltaire wrote a poem to specifically insult his rival Fréron. In fact, the whole process is called politics, and I'm afraid it will last as long as mankind does.
Does that mean we should give up any pretense of civility and take it out on an all-out Hobbesian war for our personal interests? Of course not. Many of us are lucky enough to live in countries where most attacks on political grounds are verbal only, and limited to abrasive posts on blogs or social media. (This cannot be said about less fortunate countries like Syria, for instance.) But to make 'civility' a talking point of your political standing, and using it as an argument in a political debate is just disingenuous. If you say something that I find morally repellent, I will be repelled, and state as much. If you hold opinions that I perceive to be putting my safety or individual rights into jeopardy, I will lash out in response. If we have a disagreement that revolves around my identity and can only be resolved with its erasure, there can be no debate, only conflict, until I win.
You may argue that this is all subjective, and that conservative voters may feel the exact same way regarding their own identity, etc. And you would be right. And here lies the crux of what I believe is the hidden sentiment behind all these appeals to logic, reason and civil arguments: it's not that they're deploring personal attacks and shaming per se, it's the fact that shaming someone for being right-wing works in 2018, whereas the same cannot be said for being on the left. It's not a case of 'I wish both left and right would all get along in the marketplace of ideas', it's a case of 'I wish the cultural leftward shift stopped happening so my not-so-left views were socially acceptable again'. A whole class of people is noticing their opinions are being relegated to the fringe, and they just want it to stop. This process is also part of politics, and time will tell who wins the power struggle.