As the Pew Research Center observes, for the first time in almost 25 years, "majorities in both parties express not just unfavorable but very unfavorable views of the other party." Americans, the Pew study shows, now look across the aisle with fear, anger, and contempt committed more strongly than ever to their respective teams. On college campuses, disagreements that might have been thoughtful, even friendly debates have erupted into violent melees, ending in injury and damaged property. Attacks and intimidation, it seems, have become a part of American political life.

But the conspicuousness of America's political polarization belies a counterintuitive insight: the belligerents of the nation's social and political war are actually very much alike. Culturally and aesthetically, the groups appear quite different, yet their political philosophies share a common heritage, rooted in the anti-Enlightenment ideas of the first half of the twentieth century.