Jill Lepore is a Harvard historian, a New Yorker contributor, the author of These Truths, and one of my favorite past guests on The Ezra Klein Show. But in this episode of the show, the tables are turned: I’m in the hot seat, and Lepore has some questions. Hard ones.

This is, easily, the toughest interview on my book so far. Lepore isn’t quibbling over my solutions or pointing out a contrary study — what she challenges are the premises, epistemology, and meta-structure that form the foundation of my book, and much of my work. Her question, in short, is: What if social science itself is too crude to be a useful way of understanding the political world?

But that’s what makes this conversation great. We discuss whether all political science research on polarization might be completely wrong, whether Fox News is a “villain” in the polarization story, and whether I am morally obliged to delete my Twitter account. We also talk about the missing party in American politics, why I mistrust historical narratives, media polarization, and much more.

This is, on one level, a conversation about Why We’re Polarized. But on a deeper level, it’s about different modes of knowledge and whether we can trust them.

Here’s a lightly edited transcript of part of our conversation, which we released this week on The Ezra Klein Show.

Jill Lepore

If you’re really concerned about polarization, why not leave Twitter?

Ezra Klein

I think I’m about as publicly critical of Twitter as I can possibly be. But the problem I’ve found is that everybody seems to feel that the central political conversation is there now there. I’m not saying they’re correct, but ...

Jill Lepore

I think that’s an illusion. I don’t think the central political conversation is on Twitter. Only one in five Americans has a Twitter account, and most of them never read political news.

Ezra Klein

There’s no doubt that Twitter is home to the conversation that political elites are having with each other.

Jill Lepore

But if polarization is a problem and we know that Twitter is polarizing ...

Ezra Klein

I agree that Twitter is polarizing. But what I’m trying to do there is understand a lot of the currents of opinion and where they’re coming from. It’s very hard to figure out, for instance, what the Bernie Sanders campaign is doing if you’re not watching what their supporters are saying. Twitter does help with that. So I think the difference between reporters who use Twitter well and poorly is the difference between those who use Twitter to report and those just using it to opine.

I think the problem is that the media is somewhat self-referential. And there’s no doubt that oftentimes for worse we’re in a conversation with ourselves. It’s also hard to fall too much out of that and just continue doing the job well. Maybe that’s because the media just does the job poorly. I think it would actually be totally reasonable to say that our whole definition of how news is defined is wrong.

You might just be right. It might just be that I should be off of Twitter, and I haven’t quite had the courage to say screw it.

Jill Lepore

It seemed to me that in a big structural way there’s a quite noticeable absence of villains in the book. Could you talk about that as a narrative choice? Why no villains?

Ezra Klein

I generally understand people as following incentives. I don’t trust people’s stories of why they do things. I am not a huge believer in individual agency in a narrow sense.

Obviously, if Donald Trump had not run for president, American history would have been different. But I don’t think if Mitch McConnell was beaten in Kentucky a couple of years ago that the current Republican leadership would be dramatically different. Given the incentives of the system, I think what happened was going to happen one way or the other.

So there are obviously people I think of as villains in the sense that I find their values toxic. But, what I try to do with the book is tell you how a machine works, and what happens to almost everybody in it. I don’t think of the book as relaying an argument. I think of it as a model of how to understand politics — a model that I filter new information through and that now I want to give to you. What I want to tell you is how the thing is working.

Jill Lepore

That makes a lot of sense. I wonder though if we could expand the notion of villainy, not just to individuals, as much as institutions. A person could write this book and blame the entire thing on higher education or house leadership.

Ezra Klein

The thing that I find tricky here is that I wanted to call some institutions villains, but I had a lot of trouble figuring out a chain of causality. I’ll give you an example. I am still caught in this question: Is Fox News the problem, or is Fox News a symptom of a problem? It is hard for me to tell.

Fox News obviously is driving the Republican Party. But when I look at moments when I think Fox News wanted to drive things in a different direction, things get messy. One example is when Fox News decided they were going to take Trump on in the first Republican primary debate. So, Megyn Kelly and Chris Wallace and Bret Baier really laid into him about things he said before about how Canadian health care is great and all the terrible things he said about women. So, Trump gets into a fight with Fox news and wins. Fox basically submits to him a year later: Megyn Kelly is gone, and now you’ve got Tucker Carlson channeling Trump at the 8 pm hour.

The same holds with politicians. There’ve been a number of Republicans who have tried to challenge Trump — Justin Amash, Mark Sanford, Bob Corker, Jeff Flake — and they just get destroyed as did the 16 Republicans that Trump ran against. So, on the one hand, clearly Donald Trump is an individual — is an agent who made decisions that really changed the structure of American politics. But clearly it wasn’t just him. He had figured out what was true about the audience.

So, I’ve had trouble assigning the causality or even figuring out where it begins. All of these things seem to be in a dynamic relationship with each other. So it is hard to figure out whether if you replaced a given player or institution you would really get a different result.

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