Is Trump success attributable to liberals?

S.E. Cupps:

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I have a different explanation for ascendant Trumpism. It isn't the result of conservatism but of liberalism. Thanks to unrelenting demands by the left for increasingly preposterous levels of political correctness over the past decade, people are simply fed up. Trump survives -- nay, thrives! -- because he is seen as the antidote, bravely and unimpeachably standing athwart political correctness.

The new era of liberal political correctness -- in which colleges designate "free speech zones," words like "American" and "mother" are considered discriminatory, and children are suspended from school for firing make-believe weapons -- has reached critical mass. If not for the loony sensitivities foisted upon us by the left, someone like Trump would be immediately dismissed as unprofessional and unserious, an incoherent blurter. Instead, he's the equally extreme response to extreme correctness -- if everything is offensive in Liberalville, then nothing will be offensive in Trumpland.

It's all absurd, of course. Trump says things that are unequivocally offensive, and regularly. But conservatives (and even comedians) have reached their limit on political correctness. And so Trump supporters will justify nearly everything he says, no matter how bizarre or unbecoming.
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In a previous attempt to try to explain Trump, Cupps argued that he was a Republican moderate now.  She recognizes that he has at some times embraced liberal ideas like single payer health insurance and assault weapons bans.  She also makes a point of the hypocrisy of the left on their own political correctness where they absolve insensitive things said by their own, such as Joe Biden.

The political correctness has reached critical mass levels of crazy especially on college campuses, and Trump is a refreshing response to the nonsense even though it is still hard to see him in a diplomatic context.