>(One major difference between the antebellum period and now is it's a little harder to see precisely what the cleave-line is that has America's hands around its own throat. In hindsight, slavery was obvious. But the battle lines here are not so brightly drawn... Class? Faith-based conservatism vs. modern cosmopolitanism? Tech savviness vs. technophobia? Possibly enough of all three to make a crisis).
It's two fundamentally irreconcilable worldviews, which are alluded to in TFA.
FTA:
>>One grievance that drove support for Donald Trump in 2016 was that American coastal elites felt more connected to elites in other countries than to their fellow Americans in the heartland. And there was some truth to that! There’s also truth to the European version of it—that some elites in France and Germany and Britain feel closer to one another than to the working stiffs in their own countries.
>>Interestingly, there have been attempts to counter this international network of elites with an international network of Trumpist nationalists (however ironic that may sound). I can actually imagine this kind of international populist tribe becoming a stable part of a global community—but this isn’t the place to elaborate on that long-term scenario (which I’ve done elsewhere). My main point is that one big development of recent decades—the formation of international tribes whose cohesion sometimes comes at the expense of national cohesion—was bound to happen, given the direction of technological evolution; and it was bound to be turbulent.
>>And, leaving aside the inherent tensions of moving toward a global level of social organization, there are lots of other digital-technology-abetted (and sometimes specifically social-media-abetted) problems to worry about. Like QAnoners and other conspiracy theory tribes. And violent political extremist tribes. And intense animosity among even less extreme ideological tribes. And so on.
Wright (the OP) is sort of taking this for granted, and the phrase "global level of social organization" sounds pretty benign - lots of people from different cultures all over the world, getting together and organizing humanity ... sounds great, like the plot to a Star Trek: The Next Generation episode. Anyway, the two irreconcilable worldviews are wanting this to happen and thinking it's good and inevitable, and not wanting it and thinking it's terrible and represents an erasure of national and cultural identity.
To your point, about past presidents, it would be very very helpful if people on the left and right would just be honest about all of this. Instead it gets cloaked in a lot of technobabble or scorn or just taken for granted because, again, how could anyone possibly disagree with a global organization of humanity unless they're racists, right? That's the future we've all seen in the more utopic science fiction over and over again. Whether this leads to a hot conflict within nations, or just remains a cold-but-simmering civil war is a separate question.