The Z Man attempts an explanation of what the holy hell is going on here:
The great reordering that is under way is due to the collapse of the raison d’être of the American ruling class. What animated politics in America for the last several generations has been the interplay between Progressives and the defenders of the status quo, played out in the shadow of the Cold War.
The Left collapsed as an intellectual movement when the Cold War ended, but the Right collapsed as a pragmatic alternative. You can’t have one without the other. In a single generation, the Left has adopted the economics of the Right and the Right has adopted the politics of the Left. Neither side has a reason to exist outside of naked greed.
Then again, greed is as powerful a motivator as, well, power. And it’s not like parties or factions are glued to the space they’re presently occupying. For now, though, the political discourse is basically “We’re great and you suck,” despite a total absence of detectable greatness anywhere in the spectrum.