Freedom to be Hillbillies

Reason:
But there's another major piece of the puzzle, and it would be a profound mistake to overlook it. Overlooking it was largely the problem, in the first place.
Trump won because of a cultural issue that flies under the radar and remains stubbornly difficult to define, but is nevertheless hugely important to a great number of Americans: political correctness.

More specifically, Trump won because he convinced a great number of Americans that he would destroy political correctness.