Polarization has defined American politics for several years now. More and more, it seems, Americans are divided over nearly every issue of import — race, immigration, terrorism, trade, social policy.

The divisions run deep and cut across a number of cultural fault lines.

Jonathan Haidt is a social psychologist at New York University and the author of The Righteous Mind: Why Good People are Divided by Politics and Religion.

Haidt’s research focuses on the links between moral intuitions and political beliefs. His work is especially useful now because it explains how emotions and core value judgments drive political behavior. After a presidential campaign dominated by rhetorical appeals to cultural wedge issues, Haidt’s insights are worth considering.

I spoke with Haidt about tribalism, the future of multiculturalism in America, and whether he sees a path forward after a punishing and polarizing presidential election.

A lightly edited transcript of our conversation follows.

Sean Illing

I’ve spoken to several friends who voted for Trump, and many of them can’t tell me why they did so. As a social psychologist, how do you think about Trump’s appeal?

Jonathan Haidt

Well, it’s obvious that there’s not a clear philosophy. Nor is it clear what Trumpism actually is. What is clear is that there are a number of problems in our democracy that are leading to increasing levels of anger, and Trump identified those, tapped into them, and spoke directly to the fears and anger people are feeling.

Many people talked about the economic trends and the dislocation we’re seeing. I think the economic trends are much less than half the story, and to the extent that they matter, they matter through social processes.

I’ve been fascinated by how American politics used to look so different from European politics until 2015 and 2016, but that has changed. I think that diversity, immigration, and multiculturalism are right at the heart of the sociological problem in Western democracies, along with the new and pernicious role of social media.

Sean Illing

The conversation in Europe for some time has been about the pitfalls of multiculturalism. Do you think multiculturalism has failed in Europe? And are we witnessing an extension of that failure here?

Jonathan Haidt

My focus is typically on the sacred values of any group, whether it’s on the left or the right. The sacred values of the left the and right grow out of the 19th-century conflict between labor and capital. This was filtered through the battle between communism and capitalism in the 20th century. This is what the left and right has been for most of the past 150 years.

But with the rise of the new left in the 1960s in America and in Europe, a new set of issues comes to the fore. The concerns now are around civil rights, women’s rights, gay rights, all of which are important and all of which involve high moral stakes.

Sean Illing

How does this ideological rupture in the 1960s alter these sacred values?

Jonathan Haidt

The new sacred values on the left are about anti-racism and fighting discrimination — this has been at the heart of the progressive projects since the 1960s. And this is the force behind multiculturalism. And the best way to understand this moral worldview is to look at the lyrics to John Lennon’s song “Imagine”: “Imagine there are no countries / it isn’t hard to do / Nothing to kill or die for / And no religion too.”

So this is one side of the new divide, the multiculturalism side. You may call it the globalist side, although it’s not so much global trade as the free movement of people and the unity of all mankind, all humankind.

As multiculturalism is emphasized more and more, there emerges a reaction against it on the right, which is attractive to the authoritarian mind and also appeals to other conservatives. And this, I think, is what has happened, this is what Trump is about — not entirely, of course, but certainly this is a big factor.

Multiculturalism and diversity have many benefits, including creativity and economic dynamism, but they also have major drawbacks, which is that they generally reduce social capital and trust and they amplify tribal tendencies.

Sean Illing

It’s impossible to miss the undercurrent of tribalism here. With Trump, it’s less about policy and more about cultural paranoia. The people to whom he speaks are concerned, at a very abstract level, with moral order and diversity and cultural change. It’s easy to dismiss as racism or nativism, but I think it benefits all of us to understand some of the core values driving this reactionary shift in our politics. Plenty of racists voted for Trump, but not all Trump voters are racist. We should understand their votes as well.

Jonathan Haidt

I’m a fan of the political scientist Karen Stenner, who divides the groups on the right into three: The laissez-faire conservatives or libertarians who believe in maximum freedom, including economic freedom and small governance; the Burkean conservatives, who fear chaos, disruption, and disorder — these are many of the conservative intellectuals who have largely opposed Trump.

And then there are the authoritarians, who are people who are not necessarily racist but have a strong sense of moral order, and when they perceive that things are coming apart and that there’s a decrease in moral order, they become racist — hostile to alien groups including blacks, gay people, Mexicans, etc. This is the core audience that Trump has spoken to.

That’s not to say that most people who voted for him are authoritarians, but I think this is the core group that provides the passion that got him through the primaries.

Sean Illing

What you’re describing sounds like an expansion of the culture war. Is it your view that culture wars have subsumed all of our politics and that policies are just props in this broader battle?

Jonathan Haidt

There are existential questions at stake, and this election has felt really apocalyptic for both sides. The right thinks the country is crashing into a void and that Trump, while crazy, is our only hope. The left thinks Trump will bring about a fascist coup, a war with China, or a betrayal of our alliances.

So there is an apocalyptic feeling here. Sacred values are at stake. There really can be no compromise between these two visions.

Sean Illing

Tribalism and politics don’t mix well, but I wonder if you think all politics is, on some level, identity politics. If politics is about the assertion of values in the public space, and if values are bound up with personal identity in all sorts of ways, is there any way around this trap?

Jonathan Haidt

I don’t know. A multiethnic society is a very hard machine to assemble and get aloft into the air, and if you get it just right, you can get a multiethnic society to fly, but it easily breaks down. And identity politics is like throwing sand in the gears.

Politics is always about factions, always about competing groups. At the time of the founders, those groups involved economic interests — the Northern industrialists versus the Southern agrarians and so on.

But in a world in which factions are based on race or ethnicity, rather than economic interests, that’s the worst possible world. It’s the most intractable world we can inhabit, and it’s the one that will lead to the ugliest outcome.

Sean Illing

So what next? How can we improve our democracy moving forward and cut across these racial and cultural cleavages?

Jonathan Haidt

We haven’t talked about social media, but I really believe it’s one of our biggest problems. So long as we are all immersed in a constant stream of unbelievable outrages perpetrated by the other side, I don’t see how we can ever trust each other and work together again.

I don’t know what we’re going to do about social media. I’m hopeful that future generations will learn social media responsibility and somehow manage to communicate without demonizing the other side.

We have to recognize that we’re in a crisis, and that the left-right divide is probably unbridgeable. And if it is, we’ll have to give up on doing big things in Washington, and do as little as we possibly can at the national level. We’re going to have to return as much as we can to states and localities, and hope that innovative solutions spring from technology or private industry.

Polarization is here to stay for many decades, and it’s probably going to get worse, and so the question is: How do we adapt our democracy for life under intense polarization?

Sean Illing

There are some who think we’re not quite as polarized as it seems. The idea is that what often appear to be deep divisions are really just products of people living in echo chambers, and that this amplifies differences and obscures commonalities. I’m not terribly persuaded by this, but perhaps it’s worth considering.

Jonathan Haidt

There’s certainly a debate among political scientists about this, but I’m a social psychologist, so I’m not looking at people’s views about policy; I’m looking at their views about each other. And if you look at any measures of what people think about people on the other side, those have become vastly more hostile. That’s what concerns me.

In the 1960s, surveys asked people how they’d feel if their child married a Republican or an African American or a Jew, and back then some people really didn’t want their kids to marry someone of a different ethnicity, but a different political party wasn’t as big a deal. Now the opposite is true. So I’m quite confident that there is affective polarization or emotional polarization in recent years.

Sean Illing

Are we witnessing the failure of the American political experiment, or the idea of America as a melting pot?

Jonathan Haidt

Well, I think that’s exactly the divide: Is America a melting pot, or is the melting pot, and the concomitant assimilation, a form of cultural genocide? As a product of assimilated Jews, my mother always told me that America is the promised land for Jews, because it basically just got out of their way and allowed them to assimilate and then succeed. And that was true for many other ethnic groups.

So what do we do now about our multiethnic democracy? Do we try to assimilate and emphasize our similarities, or do we celebrate differences and endorse multiculturalism?

This is exactly what we need to debate and discuss as a country, and my vote is firmly for emphasizing assimilation, similarity, and unity — this, I think, is the best way to have a multiethnic democracy.