Things have been deteriorating for a long time, much in part from liberals branding themselves as peace, love, smart, tolerant - and demonizing those who disagree as bad, hate, stupid, irrational, intolerant.
It denies the other side legitimacy of their position while simultaneously upholding liberals as everything good. But reflexively namecalling the other side when they speak hurts dialogue and the ability to even have a dialogue.
And now the authoritarian left is physically attacking those who express contrary views (because their so called hate speech is an emotional attack on the SJW pure self, so they can respond by tearing up signs and assaulting people). It is hard to have a civil debate with someone who says debating them is hate, they can passively aggressively shove you for ten minutes without consequence but the moment you push back they scream you attacked them and report it - or as happened with Milo Yianapolis, Ben Shapiro and other conservative personalities on stage and in public, attacked physically on stage with blows after being drowned out by chanting and air horns for minutes.
But it is the conservatives who get called intolerant when liberals enter private gatherings of conservatives to silence them, who attack Trump supporters in San Jose and say it is fighting intolerance, the conservatives who are blamed when liberals riot to shut down conservative events.
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