"A sophisticated, nuanced approach to a reform of the Democrats' identity politics could have worked well for the Republicans. Many Democrats themselves are suggesting they went overboard. But nuance and sophistication have no place in Mr. Trump's approach. He won via the politics of polarization."

There is no sophisticated, nuanced approach on either side. Trump retaliated in a tit-for-tat way, swinging the US from one extreme to its mirror image.

The Democrats are the ones who had succeeded in polarizing the electorate, it was easy for Trump to reap the rewards.