Political correctness is the un-codified prohibition prohibiting blasphemy against liberalism. To speak negatively about a liberal cause might easily cause the loss of income, provoke an IRS audit or bring down SJW wrath. It is the stifling of free speech. It the suppression of reason and the preemptive defeat of the opposition to liberal goals. It is inherently unjust and socially toxic. It is the revocation of the first amendment without all the trouble to call for a repeal.
Thanks to Donald Trump, PC is begining to fail.
“It the suppression of reason and the preemptive defeat of the opposition to liberal goals”
I think of “liberalism” as stealth totalitarianism. At least the communists and fascists had the decency to tell us what they were up to.