Recent shootings — from the attempted attack on congregants observing Yom Kippur at a synagogue in Halle, Germany, in October, to the killing of 51 worshipers at two mosques in Christchurch, New Zealand, six months ago — have been tied to the promotion of anti-Semitism, Islamophobia and hate-fueled violence on the Internet. When far-right extremism goes viral online, the contagion infects flesh-and-blood human beings capable of materializing their hate by force.

So what do we do?

While restricting Internet hate speech is important, we might also consider devising a counterattack. Almost a century ago, when Jewish advocacy groups confronted the spread of fascist propaganda in the United States, they cooperated with other organizations and American mass media to produce counterpropaganda. This history shows that when social activists and media industry professionals join forces, they can mount a formidable challenge to the toxic rhetoric of the far right.