The obstacles to a bipartisan turn have been set forth even more forcefully. Josh Barro focused on the ways that Trump shortsightedly put himself in a weak negotiating position:

It's possible to imagine a different opening to Trump's administration that would have put him in a much stronger negotiating position. He could have started with infrastructure and tax reform instead of health care. He could have made good on his initial overtures to Democrats, offering them an infrastructure package they would have found tempting, even if it came packaged with tax cuts. He could have sprung this on Republicans at a time when they didn't feel empowered to stand up to Trump. But he didn't do those things. Now, Republicans in Congress are annoyed with the president, sniping at each other, and no longer so afraid of what can happen when Trump tweets. They've defied him once and survived — why not do it again? Democrats smell blood in the water, and are much more inclined to deny Trump assistance and enjoy his failures than to work constructively with him.

Michael Brendan Dougherty added that, for Democrats, opposition has huge upsides. “Democrats have a kind of gift in Trump, in that he's almost proven everything they ever said about Republicans, that their high church conservative rhetoric was a mask for hiding their true motivation, racial animus,” he wrote at The Week. “Trump proves that conservatives' family values rhetoric was cynical! Democrats don't need to work with Trump. The Trump presidency is already working for Democrats.”

Those arguments are persuasive.

But I think there is an even deeper dynamic that will make it very difficult for Trump to forge a coalition that includes moderate Democrats or African Americans, at least if he hopes to retain enough support from his base to get reelected.

* * *

I’ve recently published a series of articles drawing on the insights of Karen Stenner, a leading scholar of the deep forces that tend to tear polities apart. Her core insight is that democratic countries are composed of citizens with very different predispositions. In her taxonomy, “libertarians” are very comfortable with difference and diversity, while “authoritarians” have a strong, perhaps innate preference for unity and sameness, even if coercive measures are required to enforce it.

Usually, a country’s libertarians and authoritarians live alongside one another in relative peace. Under normal conditions, it can be difficult to even tell them apart.

But everything changes if those with a latent predisposition to authoritarianism are activated. Suddenly, their relative willingness to live and let live gives way to increasing demands for policies that target, repress, or punish those perceived as different.

In response, the predispositions of libertarians are awakened in turn as they perceive a threat to the diversity or difference that they value. They mobilize to protect it. The aftermath of Trump’s first travel ban is illustrative. Folks who’d never been involved in a political action reacted to news of green card holders getting detained at customs checkpoints by spontaneously flocking to airports in protest.