This professor set off a war of words over “identity politics.” We debated him.

When Hillary Clinton lost the presidency to Donald Trump, the left started grasping for an explanation.

Mark Lilla, a liberal political theorist at Columbia University and author of The Shipwrecked Mind, offered one in a New York Times essay published shortly after the election: The Clinton campaign spent too much time appealing to what he calls “identity liberalism.”

Lilla’s thesis is that the left’s exaltation of diversity is “a splendid principle of moral pedagogy, but disastrous as a foundation for democratic politics in our ideological age.”

In this election, Lilla argues, Clinton was “at her best and most uplifting when she spoke about American interests in world affairs and how they relate to our understanding of democracy.”

However, according to Lilla, Clinton too often would “slip into the rhetoric of diversity, calling out explicitly to African-American, Latino, L.G.B.T. and women voters.”

This, he writes, was a strategic error because it excluded the white working class, which was a large part of why Clinton lost the election.

The response to Lilla’s essay was fierce. Slate’s Michelle Goldberg argued his reduction of identity politics confuses the “absurd excesses of political correctness” with “race and gender politics themselves.” Vox’s Matthew Yglesias made a vital point: “The reality is that politics is not and will never be a public policy seminar. People have identities, and people are mobilized politically around those identities. There is no other way to do politics than to do identity politics.”

The most dismissive rejoinder was from Katherine Franke, a law professor at Columbia University, who compared Lilla to David Duke and charged him with “underwriting the whitening of American nationalism, and the re-centering of white lives as the lives that matter most in the U.S.” If nothing else, Franke’s screed did stumble into a relevant point: America was founded on a system of white supremacy, and contemporary liberalism is a necessary corrective to this.

Whether you agree that “identity liberalism” is a problem or not, this is a conversation the left needs to have. The sword of identity politics cuts both ways. A reliance on identity-based coalitions on one side will invariably produce an upsurge in identity politics on the other.

Trump’s success is too complicated to be captured by a single framework of analysis, but the triumph of white identity politics was a crucial factor. I’m not convinced the left is to blame for this. America is a big country with plenty of racists and xenophobes; those racists and xenophobes exist independent of the Democratic Party.

White identity politics, moreover, if not invented was certainly perfected by the Ku Klux Klan, long before progressives started making noises about equality.

Nevertheless, a strategic question has to be posed: Are Democrats, by relying so heavily on identity-based coalitions, undermining their own political project? Would they be better served by elevating issues over identities? Perhaps so.

But the fact remains: Identity is bound up with politics; Republicans, particularly with Trump at the helm, are pushing their own brand of identity conservatism; and liberals have an obligation to defend the targets of exclusion.

On Wednesday, I reached out to Lilla to hear his response to the criticism. I also wanted to press him on a few of the questionable claims he made in his New York Times essay. Our conversation didn’t resolve any of the problems, but hopefully it elucidated some of the challenges.

I think we ought to define this phrase “identity politics” at the top. What does this mean in your mind?

Well, the term I’ve been using is “identity liberalism,” and that’s important because identity liberalism, in my view, is a kind of pseudo-politics that, despite whatever one thinks of the claims being made, distracts attention away from issues and focuses it on questions of personal identity or social recognition.

Now, these are important questions, but they’re not, strictly speaking, political questions. They take our attention off of what politics in a democracy is about, namely acquiring and using power by occupying institutions. And you can only do that by winning elections at every level of government and by staying elected.

My view is that the only way to accomplish this is to present the principles of liberalism in a way that as many people as possible in the country can affirm them and feel that they resonate with those principles. So I say identity liberalism is a pseudo-politics because those engaged with it think they’re doing politics, and they are doing a kind of movement politics, but the core aim of political action in a liberal democracy is not to speak truth to power but to acquire power, and that requires persuasion and appeals to commonalities.

I’ve argued that all politics is identity politics insofar as politics involves the assertion of values in the public sphere. If you grant that values are bound up with identity, it’s not clear to me how you circumnavigate this problem.

Vox’s Matthew Yglesias made a similar point in his response to your piece, which is that politics is not — and has never been — a public policy seminar. People have identities, and they’re mobilized around those identities. And so, as Yglesias wrote, “there is no other way to do politics than to do identity politics.”

To begin with, identity can be used to mobilize people for political action — that’s for sure. But political action is something else. I certainly agree that someone’s identity may affect their political views. Again, though, democratic politics is about persuasion. It’s not about self-expression.

However you come to your values or positions, you become political the moment you enter the arena trying to persuade other people of your values. If you have a certain value and you attach to that a whole picture of your identity, and then ask the other person not only to accept your position but to accept your account of your identity, you’re setting the bar very high for political agreement.

If I can convince someone with a very different identity, or someone who doesn’t accept my account of my identity, to agree about certain principles, I can then walk that person down from a principle to a particular case.

Can you explain that last point by way of an example? What would that process look like in practice?

Here’s an example of the kind of argument you’d make: Black motorists are being targeted and mistreated by American police officers — we know this. If my principle here is equal protection under the law, and I want to convince someone who doesn’t know black people or doesn’t particularly care about the black experience, if I want to persuade that person to get engaged and care about this issue, I can do one of two things. I can get that person to agree to the principle of equal protection under the law, and then I can walk them down to saying that black motorists, as citizens, deserve to be protected.

If, on the other hand, I try to persuade that person of a certain picture of the black experience today and the injustices of the country, or what it’s like to be black or how I define myself as black, I’ve made my job much harder and increased the odds, fairly or not, that they’ll reject my message.

So I think identity politics mixes the work of social reform, which has to do with recognition and incorporation and diversity, with the work of political action, which requires political speech that encourages people to agree with you.

I understand the strategic and rhetorical point you’re making, but there’s still the fact of identity as an instrument of mobilization, which is being used mercilessly by Trump at the moment. And I think that’s part of the conundrum here: All this talk of identity politics on the left seems to ignore the fact that identity politics on the right is every bit as pervasive, and has a much longer history.

One can argue about which side committed to identity politics first, but it’s a fact that Democrats have been out of power in terms of holding on to public sentiment since 1980. Reaganism offered a picture of what the country was that we’ve not been able to replace.

If people are withdrawn into their identities, you’re writing off a whole group of people that you need to reach if you want to be elected. White people are still the majority group. If someone is withdrawn into his or her identity, the only way out of that is to appeal to something that they already agree with.

Again, I’m talking strategy here. I’m sick of losing, and I’m sick to death of noble defeats.

Let’s talk about elections in that case. You’ve seen the data showing how significant racial resentment was among Trump voters. Your contention is that this is largely a reaction against identity liberalism. But the country is in fact changing. It is becoming less white. It is, like the rest of the world, becoming more cosmopolitan. It is not the homogeneous and male-dominated culture of the ’50s.

How do we know the “whitelash” isn’t a predictable and unavoidable reaction to these realities?

We’d have to do a lot of survey research to get at not only what people’s attitudes are but what motivated them to vote in a certain way. It’s always going to be overdetermined because people are going to give you various reasons, any one of which could have been sufficient for them to vote as they did.

Certainly resentment about identity discourse was part of this. One would have to untangle that a bit to know with any precision how determinative it was, but it’s clear that it was a factor.

I’ll say this, however. The white working class that drifted away from Democrats, beginning in the ’70s: These people in their daily lives are not living in the world that you described. You’re describing the world that you and I live in because we’re educated and we live in urban areas. Many of these people don’t. They live in relatively homogeneous places, with some immigrants but nothing like you find in major cities. They live in areas that, residentially at least, are largely segregated.

So your model of the world is not the world in which many Americans live in day to day. There is the mixed, cosmopolitan world that comes to them through media, and that can feel alien to someone outside it. And if we want to understand why Democrats have lost people in these communities, why they’re voting against their own interests, we have to consider all of this.

The bottom line is that we can’t win without these people. And when I’m talking about winning, I’m not just talking about presidential elections — we pay too much attention to that. The things that get done in this country are done through legislation, which means you have to win the Congress and you have to go every state in the country. The laws, moreover, get enforced in state governments, and so you if you’re not competitive there, you can’t guarantee that the laws you pass will get enforced.

So if we care about the people we say we care about — African Americans, women, LGBT people, Latinos — if we want to protect them, symbolic victories won’t do. We have to be competitive and we have to win at every level of government, and that means sucking it up and getting the votes of everyone.

Does “sucking it up” mean pandering to cultural angst or nativist fears? Because that’s what the other side does, and it didn’t start with Trump. Appeals to black or Latino identity are dismissed as identity politics, but stories about “welfare queens” or Obama’s secret Kenyan identity are playing the same game on the other side, only in a more vulgar form.

I don’t dispute your point about identity politics on the right. My focus is on what to do moving forward, on how to win. No, you don’t have to appeal to the angst and nativist fears. My point is that you appeal to principles so you get them off this subject of identity. And the two basic principles of liberalism are equal protection under the law and social solidarity.

To be clear: I do think that the politically correct bullshit has gone too far, especially on college campuses, and that that has driven people away. But I’m not convinced that this — or identity liberalism in general — is the primary reason for the wave of reactionary politics we’re seeing, though perhaps it’s a bigger factor than I thought.

Everyone, no matter where they live, can see that the culture is changing. There is among the rural white working class a nostalgia for a bygone world — a whiter and simpler world — and that world is gone, and it’s not coming back. But Republicans dangle the possibility of its return as a way to appeal to this underlying angst.

I’m not so sure that liberals can overcome this with the broad appeals to shared principles that you recommend, though I concede I might be wrong about that.

Well, your pessimism must be right, but my article was about political strategy. Let’s say what you just said is true. These issues were lurking beneath the surface, and a demagogue came along and he pushed every button, and they became nostalgic in the way that you described. Okay, then that’s where we are.

So we have two jobs now. One is social reform, and that means winning hearts and minds, and that happens through schools and churches and television and universities. There are all sorts of ways we can work to make America more tolerant and inclusive. But we can’t confuse that work with political work. Political work is only about acquiring and using power to protect the people you want to protect.

An election is not a seminar. It is not a therapy session. It is not a chance to rewrite history. An election is only about winning, and you do what you have to do. And yes, that doesn’t mean you have to pander to people, but it may mean you have to be silent about certain things and get your apron dirty.

If you want to reform the American soul, become a minister. But if you’re serious about politics, you have to go where the people are and find a way to reach them, and not be afraid to get dirty.

You say that Democrats should focus more on broad economic themes that appeal to everyone, especially the white working class, and not just identity concerns. But the response you get from most people on the left is that economic populism and identity politics aren’t mutually exclusive, and in fact are inextricably linked.

Well, I’m not talking about economic populism. I think we have to focus on these issues insofar as we have leverage there. What I’m talking about is more ambitious. Consider Reagan, whose optimism points to the power of a view of a good collective life. JFK electrified a generation in this way. FDR did the same thing.

But now the shining city on the hill is a Rust Belt town where all the shops are shuttered and people are working part-time jobs for less money. What’s needed is a different picture of what we are as a country, something that raises people out of themselves.

And that’s what Democrats need to offer above all else.

That’s all fine and well, but that’s not the whole Reagan story. Reagan absolutely played the identity game. It wasn’t all rainbows and sunshine and a shining city on a glittering hill. There was also the fearmongering and the racial pandering and the “welfare queen” rhetoric.

Hell, he hired the master racist dog whistler Lee Atwater, whose raison d’être was helping Republicans appeal to racists without sounding racist. That was as much a reason for his success as anything else.

I accept everything you said except for the bit about that being a decisive factor in his success. In any case, you may not be old enough to remember what it was like during the Carter years. There was no sense of what the country was or what it could do. And then someone came along with this towering idea of America, and people absolutely responded to it.

But no doubt there was also the pandering and strategic capitulations you mentioned.

One of your colleagues at Columbia, Katherine Franke, argues that you’ve trivialized the “identity drama” on the left by diminishing the concrete concerns and structural disadvantages that made these movements necessary. The complaint, as I understand it, is that there’s an inherent inequality baked into the pre–civil rights era of liberalism you praise in your essay, and ignoring that undercuts your argument.

To begin with, Professor Franke didn’t have an argument. Her piece was a slur. But I’ll take up your question. Look, I agree with that picture. I understand that FDR offered a vision of freedom that didn’t apply to African Americans. That’s why we have to keep harping on these principles in order to ensure that they apply to more of us, to everyone.

Someone like Franke, who’s wrapped up in these identity questions, is really asking for recognition of what’s happened. When people ask me to recognize any of these injustices, I eagerly accept them. Again, my point was strategic and political: Do we run on this? No, we run on something else.

We run on something that wins, and then we make the country most just and equal.

Another concern I’ve heard on the left, and this was articulated nicely by Slate’s Michelle Goldberg, is that you’ve conflated the illiberal excesses of the “social justice warriors” with race and gender politics as such, and these are not the same things.

Do you take this point at all?

I want to distinguish political discourse from general cultural discourse. In general cultural discourse, there’s a lot to be said about race and gender, and talking about it has led to extraordinarily positive changes. Making these arguments is critical to mobilizing people, and I didn’t say that in my article.

But when it comes to seizing power, that will not win you a single election. It will not pass through the spam filter of Fox News. Appealing to principle is our best chance of passing through the right-wing media filter.

In your essay, you say liberals should respond to the legitimate threats to minority groups with a “sense of scale.” That’s an awfully vague phrase — what does it mean?

I mean it in two senses. One sense is that one of the problems with the development of identity politics in the ’70s is that it was about group identity. Society said you’re a black man; therefore you belong in this category. Or this is how you make love; therefore you’re a homosexual and you belong in that category. A form of identity politics grew up around these categories. But then there was a shift from group identity to personal identity. The problem, however, is that if you’re focused on yourself and not a wider historical horizon, you tend to be more myopic in your concerns.

What I did not mean by a “sense of scale” is that we shouldn’t be responding to all of these injustices that are being committed against women or African Americans or LGBT people.

My point is that we can only protect people if we have power.

A party is necessarily a reflection of its constituencies. Many of the so-called “identity groups” are loyal Democratic voters, and for reasons that have to do with more than their identities. So Democrats can’t risk alienating these (growing) constituencies in an effort to win over swaths of white America that, frankly, are already disposed to vote Republican for cultural reasons.

So how do Democrats thread this political needle?

They have to recognize that, historically speaking, this is a new development in the Democratic Party. For a long time, you could divide the party into interests and major issues, i.e., education or labor unions. But what happened after the ’70s is that the party split up into various identity groups with essentially overlapping positions on most of the relevant issues.

Republicans, alternatively, are not like this. Before Reagan, the party was split in similar ways. What Reagan delivered was a broad message with a couple of undergirding principles, and the party consolidated into a loose coalition of interests without any identity-based divisions.

Well, much of this is a function of the constituencies themselves. The fact is most of the Republican Party is white, so the lack of diversity is itself a big reason why you don’t see these same coalitions forming.

At any rate, we’re just about out of time, so let me ask you this final question: What does a post-identity liberalism look like? These racial demons have already been unleashed. The reactionaries on the right are already charged up and will not go quietly. So the groups of voters who tend to vote for Democrats are going to be under assault in this country.

How does the Democratic Party defend them without leaving themselves vulnerable to critiques like yours?

Simply put, it has to try to win. Defending people is not something that’s done by setting up a new center for the study of identity at a university. If you actually want to defend people, you must hold power. And to hold power, you must win elections. The logic of this is inexorable. This has to be our focus.

I’m as worried about these issues as any of my critics. I want to get to a point where a white working-class guy in Flint, Michigan, with his lousy water, sees a black man being beaten by police on the television and says to himself, “That could be me.” I want him to sympathize.

If you drive home the point that we’re all citizens, we’ve got a chance of doing that. But if you make this into a story of black America and white America and ask people to accept this identity or this version of history, you are giving them countless ways to not give a damn.

The only way to reach over that and get people to sympathize with each other is to make them believe that we share something.