The London-based start-up, Moonshot CVE, has worked with the Anti-Defamation League and Gen Next Foundation, a philanthropic organization, to develop a pilot program tailored for the United States. It ran for several months last summer, and senior counterterrorism officials have endorsed the method.

“I think in general that U.S. government work in the prevention space has been a little bit slow in coming, but this strikes us as a very worthwhile program that should continue,” said Russell E. Travers, acting director of the National Counterterrorism Center. “Anything you can do to stop individuals from consuming the kind of very gruesome radicalization potential that you see on the internet and take them someplace else — just common sense tells me that is a good thing to do.”

Moonshot was created by Vidhya Ramalingam, an American, and Ross Frenett, who first studied extremism in his native Ireland. Both worked at a London think tank that focused on Islamic and other forms of extremism issues before they founded Moonshot CVE in 2015. (CVE stands for Countering Violent Extremism.)

At that time, most online efforts were geared toward expunging content. Such efforts might interrupt the activity, but did not address the underlying problem as Moonshot seeks to do. “Rather than police content, it would try to disrupt the process of radicalization,” said Clark Hogan-Taylor, the head of communications for Moonshot.

The effort to be unveiled in the coming months in the United States will respond to a wide range of search terms. Moonshot, which previously developed 48 ads, now has 1,064. Five playlists expanded to 86.