This is the part of the article I think is most true:
If working-class whites fear annihilation and obsolescence, that's not entirely irrational: For decades, Republicans have advocated and enacted policies that harm their own voters.
This is an old American story, built on divide-and-conquer tactics and the "psychological wages of whiteness." White people with money and power know how easy it is to manipulate poor and working-class white people through appeals to white supremacy, racial resentment, entitlement and fear. In the immortal words of Lyndon Johnson, "If you can convince the lowest white man he's better than the best colored man, he won't notice you're picking his pocket. Hell, give him somebody to look down on, and he'll empty his pockets for you."