As someone who teaches about the potency of nationalism, it's hard not to notice that the nationalist narrative has achieved total victory in the US. Political discussion is almost entirely centered around cultural/identity issues, which strongly benefits nationalist politicians.
In the American South, this is a narrative that has dominated since at least the early 19th century. But ever since Nixon, national discourse has moved in the same direction (and is largely responsible for the southern realignment).
In contrast to the liberal and socialist emphasis on economics, nationalism highlights group identity and conflict. Political disputes are no longer over distribution of resources but over who a "proper" American is and what should be done to those who fail to make the cut.
Fear and anger become the norm. Everything boils down to loyalty to one's group. Getting votes requires proving you're on your tribes side, not on policy preferences or ability to deliver. Economic policy has losers and winners, but nationalism appeals to the entire majority.
This allows the creation of previously unthinkable coalitions; between rich and poor, educated and uneducated, capital and labor, secular and religious. Once created, any attack on this coalition is seen in identity terms, especially if it comes from another ethnic/racial group.
The left, focusing on economic issues, has seen its political power wiped out in places as diverse as Poland, Hungary, India, and Israel. Its ethnic majority voters defected to parties blaming minorities/foreigners for the majority's economic troubles.
That brings me to the US, where Trump has completed Nixon's mission of shifting discourse from economic issues - which benefit the DNC, especially with the poor - to social/identity ones. Attacks on Trump are now seen as attacks on the white identity. Which means he won.
Even attacking Trump on his tax policy, which unambiguously hurts the poor, is seen as an attack on white identity. Once a country hits this point, it's nearly impossible to reverse. We're far more likely to see nationalists outbidding Trump (see Moore) than a return to normalcy.
Anyone reading this for solutions: sorry to disappoint you, but there really aren't any. The best hope is that the nationalists in power screw up in such monumental and definitive ways that their supporters awake from their nationalist stupor. Or rely on demographic change. /end
79% of white non-college-educated men (the group most susceptible to nationalist appeals) are supporting a historically bad candidate because of his identity-based appeals. There is something to be said for nationalists frequently choosing deeply flawed candidates (guess why?). 
