This past week, the right-wing political activist Charlie Kirk was assassinated at Utah Valley University. Kirk, a close ally of President Donald Trump’s, was thirty-one years old. Tyler Robinson, a twenty-two-year-old Utah resident, has been accused of the murder. It is the latest in a string of attacks on American political figures: the shooting of two Minnesota state lawmakers and their spouses in June, two attempts on the life of President Trump during last year’s Presidential campaign, and the January 6, 2021, storming of the Capitol, to name a few.

I recently spoke by phone with Lilliana Mason, a professor of political science at the Johns Hopkins S.N.F. Agora Institute and an expert on political violence. In 2022, she co-wrote, with Nathan P. Kalmoe, the book “Radical American Partisanship: Mapping Violent Hostility, Its Causes, and the Consequences for Democracy.” During our conversation, which has been edited for length and clarity, we discussed what makes our current era potentially more dangerous than the late nineteen-sixties, the connection between partisanship and political violence, and how to tone down partisanship when your political opponents really are extremists.

When it comes to political violence, what feels different to you about our current era?

We have been collecting data on people’s attitudes about political violence in the United States since 2017. But there is some older data that we have from newspapers, and from the Pew Research Center, which actually shows relatively similar levels of approval for political violence to what we see in the Trump era. So I don’t think that there’s a punctuated point at which the era of political violence begins. We can say that there certainly was significant political violence in the nineteen-sixties. But the difference then was that it was not organized along partisan lines. And what we’re seeing today is organized along partisan lines.

What do you mean by “organized along partisan lines”?

I mean that it is coming out of an animosity between the Democrats and the Republicans. In the sixties, there was a lot of violence, but it wasn’t like the Democrats and Republicans were on two sides of that violence. It didn’t line up perfectly with politics, or at least not in terms of partisan politics. Back then, it could be kind of random. But when the parties are helping organize the animosity, the violence itself can become more institutionalized.

That’s interesting, but, in the current era, when we read about the people who commit political violence, they often don’t sound like typical partisans. They have weird and strange views, and sometimes crazy views. How do you synthesize that with what you just said?

So one way to think about it is that there is a kind of political violence in which a political figure is targeted to achieve political goals. I think that everyone would agree that that is political violence. A lot of what we’ve been seeing recently, even just over the last year, has been violence targeting a political figure for nonpolitical ends or for maybe dubiously political ends. And in fact, these attacks are almost more like school shooters, where it’s a disturbed young person who’s trying to get attention and wants to go down in history. It’s violence against a political figure, but it’s not entirely because they want to achieve a political goal. Are you attacking the person because they’re political, or are you attacking the person because they’re famous? And I think it’s really easy to confuse those two things. But I think that the goal of the attacker does matter.

Do people in your field think that the partisan, toxic atmosphere in the country could be motivating these attacks, even if the shooters themselves aren’t clear partisans attacking someone from the opposing party?

A lot of political violence is done by people who are going to be violent anyway. Some people are just sort of like a loaded weapon, and the question is, where will they aim? And that’s where political leadership has power. Political leadership can tell these extremely volatile people what an appropriate target is. And so they might have exploded in one direction if they weren’t paying attention to politics or if they didn’t have leaders telling them who to hate. But because of the political environment, they turn in that direction. So I think in a sense it’s not necessarily telling them to go be violent; it’s that these are usually unstable people already and it is about where their attention is being drawn.

I want to go back to 1968. The lack of the same level of partisanship, and the lack of leading Democrats and Republicans advocating violence in the same way they are now—even when those politicians were doing other terrible things, like pursuing the Vietnam War, that unsettled the atmosphere—makes me think that democracy was less threatened then. Is that your view?

Empirically, it is different, right? It is different because the type of violence that we’re seeing right now, or at the very least, the type of animosity that is motivating violence, is very much about who is a Democrat and who’s a Republican. I think that’s more dangerous than an era of chaotic political violence, because our parties structure everything. When we go into the voting booth, we think we’re voting for a political agenda, but we’re also voting for these questions many of us consider existential. Having violence embedded into that, there’s a potential for violence becoming embedded in our politics itself.