It happened when John F. Kennedy appeared at his presidential inauguration without a hat. One instant of astonishment, followed by men’s hats instantaneously dropping out of style.
It happened when Michelle Obama began appearing sleeveless as First Lady. A few days of disdain and mockery from the right, after which virtually every female commentator on Fox News had shed her sleeves.
And currently, it has happened with Donald Trump’s unfiltered attacks on anyone who dares to question or oppose him. After excoriating the president for his vitriol and divisiveness, his detractors on the left have used the exact same tactics in their campaign against him.
This has nothing to do with taking sides.