Do you normally read Edsall? He's well reasoned the majority of the time. He seems to have jumped off the deep end of despair, however. His data in this piece is countermanded by your (correctly) pointing out that Democrats made red districts competitive, and furthermore made republicans spend way more money that they thought they'd have to defending Montana and suburban Atlanta. But of course they still lost. Because the energy well is too deep.

The problem at hand is explained mostly by the big sort. Instead of living in one two party country, we're living in two one party countries. No one has ever explained the trap of living under one party rule better than Kundera in The Joke. Similarly to the communists, the GOP (and the Democrats to a lesser extent) have decided that loyalty to the ideology is paramount, so they've encouraged a system where going against orthodoxy gets you excommunicated. In this situation, everyone tries to out do themselves to show that they're the most righteous. Steps can be taken toward further purity but not backward to debate and reason.

In The Joke, "Long Live Trotsky" was enough to get a true believer sent to a work camp. In the GOP, suggesting that carbon dioxide is a pollutant can do the same (metaphorically). Same goes for taxes, public education, 'political correctness', etc. Ideological purity on all these issues is the only way to ensure survival and acceptance, and when a purer-than-thou candidate shows up, you'd best adapt (e.g., Luther Strange, who by almost all reasonable analysis is a right wing extremist, yet fell short in the shithole that is Alabama). (I could go on a long diatribe about ideological purity in the democratic party, but their issues are less existential, IMO.)

Unemployment or drugs didn't cause people to vote Trump. People vote Trump and do drugs and have high unemployment because everyone who had the chance has already moved to New York and L.A. and Seattle. The only way to make those areas competitive again is to get their economies growing, and the only way to do that is to attract human capital. I'm sure as fuck not moving there, and I don't know anyone who would.