(CNN) When Donald Trump ran for president, one of the core pillars of his pitch to the voting public was this: Political correctness is a cancer eating away at the body politic.

"We have to straighten out our country, we have to make our country great again, and we need energy and enthusiasm," Trump said during an appearance on "Meet the Press" in August 2015. "And this political correctness is just absolutely killing us as a country. You can't say anything. Anything you say today, they'll find a reason why it's not good."

People responded -- big time. The idea that liberals and/or the elites had made it so that no one could say what they thought, for fear of being labeled intolerant or un-enlightened, was a powerful one in the very communities that Trump was appealing to: Whites watching the society and culture they had grown up with change faster and in ways that, in some cases, made them deeply uncomfortable. ( Exit polls in 2016 showed Trump got 57% of the white vote, 8% of the black vote and 28% of the Hispanic vote).

Like much of Trump's appeal, there was a kernel of truth in it. Speech -- on places like college campuses, for example -- had been curtailed over recent years by usually liberal groups insisting offense and demanding "trigger warnings" in classes and quads. There was a frustration among many that having views that diverged from what liberals had decided was acceptable were being shouted down.

The problem with Trump's assault on political correctness is that he took it so far that he clearly emboldened not only those lurking in the shadows to bring their hate speech into the light of day, but also lowered the overall bar for what is considered acceptable discourse among politicians and other leaders in the country.