You make a lot of good points, but the “He’s with Me” vs. “I’m with Her” trope is overstressed and oversimplified, so it actually weakens your analysis.

My own favourite arguing point is that Trump’s popularity is actually a protest against correctness — the PC Police have only themselves to blame for his popularity. Trump is to conservatives what George Carlin was to liberals: someone who gleefully says forbidden, naughty things with total disregard for whom he might be offending.

But that’s not the whole story either. In fact, there is no simple encapsulation that can explain what is happening (although after the fact I’m sure sociopolitical theorists will make up a bunch of them, and one or two will become the accepted explanations). When hundreds of millions of individuals, each with a complex set of beliefs and motivations, interact this strongly, collective behaviour will always emerge that no one expected.