The Internet may be losing the war against trolls. At the very least, it isn’t winning. And unless social networks, media sites and governments come up with some innovative way of defeating online troublemakers, the digital world will never be free of the trolls’ collective sway.

That’s the dismal judgment of the handful of scholars who study the broad category of online incivility known as trolling, a problem whose scope is not clear, but whose victims keep mounting.

“As long as the Internet keeps operating according to a click-based economy, trolls will maybe not win, but they will always be present,” said Whitney Phillips, a lecturer at Humboldt State University and the author of “This Is Why We Can’t Have Nice Things,” a forthcoming book about her years of studying bad behavior online. “The faster that the whole media system goes, the more trolls have a foothold to stand on. They are perfectly calibrated to exploit the way media is disseminated these days.”

“Troll” is the fuzzy term for agitators who pop up, often anonymously, sometimes in mobs, in comment threads and on social networks like Facebook and Twitter, apparently intent on wreaking havoc. The term is vague precisely because trolls lurk in darkness; their aims are unclear, their intentions unknown, their affiliations mysterious.