Sly, snotty, and often irresistible, snark has been flourishing in the petri dish of the American media for decades now. The Internet, however, has spread the contagion faster than ever. And according to New Yorker film critic David Denby, we may be reaching a new level of toxicity. That’s the gist of his slender new polemic, whose tongue-clucking subtitle pretty much says it all: Snark: It’s Mean, It’s Personal, and It’s Ruining Our Conversation. In a phone interview with CJR’s James Marcus, the author discusses his motives for writing the book, the epidemic of unease among established journalists, and the faint hope that the runaway train of snark can be slowed to a respectable crawl.

Let me begin with a question about the genesis of this project. If modern, American-style snark has been around since the heyday of Spy in the eighties, what made it imperative to write this book now?

As I mentioned in the acknowledgements, the specific genesis was a dinner with [Slate founder and freestyle pundit] Mike Kinsley last March. We both had the same idea, and I think he was going to do it for Time magazine, but he ceded the turf to me. What was really getting to me, though, was the thought that Barack Obama might be done in by coded racist comments. Snark was the vehicle for those attacks: an appeal to “understood” notions among Republicans that this guy was alien, un-American, not right for leadership. Now, it turned out I was wrong. Obama was our Democratic Prince! And a lot of people, including Republicans, wanted to protect him in a way that most of us won’t be protected.

Were you returning fire in any sense?

There was no personal motive. I mean, I’ve been snarked like everybody else, but no more than other people. I just kept seeing the same kind of formulation in all sorts of places, including The New York Times. I sensed that Gresham’s Law was beginning to operate: because everyone wants to be funny in this country—which is actually very hard—the bad stuff was driving out the good stuff. And there’s going to be more and more of this, particularly because everyone in journalism is anxious. Older journalists are terrified of being left out of it, of not seeming hip, while the younger ones are battering at the gates trying to get in.

You write that one of the optimum cultural conditions for snark occurs when “a dying class of the powerful, or would-be powerful, struggles to keep the barbarians from entering the hallowed halls.” Are traditional journalists such an embattled class?

I think so. I just feel this tremendous collective anxiety among established journalists that somehow they’ll be left out. There will be a game of musical chairs and they’re not going to get a chair. So one way of seeming to embrace new media, one way of staying in the game, is to get snippy and sarcastic and snarky. They’re certainly not encouraged to be more analytic, more intelligent. I adore Josh Marshall—he’s the best thing to come along in years. But for every one like him, there are five who are just fucking around, trying to grab a little piece of our attention.

Snark, as you note, is not always easy to pin down. Its main identifying marks seem to be reflexive contempt and what you call “the little curlicue of knowingness.” Does that sound accurate?

Yeah. It’s not hate speech, it’s not trolling, it’s not simple insult. What I’m getting at is contempt, and a signal sent to a member of a club (which can be enormous or tiny) in which a certain kind of reference is understood, and stands in for an attitude that one wants to put down.

You do provide a potted history of the form, starting with Juvenal and the other great snark merchants of the classical era.

It’s a bit of mock scholarship. But I wanted to suggest that there’s a certain sensibility that grew, and to contrast the formal rules of invective in the ancient world with what we’ve got now.

James Marcus is the deputy editor of Harper’s Magazine. His next book, Glad to the Brink of Fear: A Portrait of Emerson in Eighteen Installments, will be published in 2015.