After the election of Donald J. Trump, technology companies like Facebook, Twitter and Google have been called to account for magnifying the anger and misinformation of the voters who helped propel him to the presidency.

Facebook and Google, for example, have both carried fake, frequently incendiary, articles that were highly shared by their users; Twitter has allowed those kinds of stories to proliferate as well, while also becoming a proxy battlefield where far-right hate groups organize and recruit, frequently targeting women and minorities on the site.

The leaders of these tech businesses say they are neutral platforms that shouldn’t try to police political debates. Facebook explains that it can’t be held accountable for the material shared on its site because it is not a news organization.

Nice try. These sites are not neutral platforms, but robust businesses that have financial incentives to share fake news and encourage their users to stew in their own hateful juices; the more they stew, the more time they spend on the site. In the case of a fake news story that claimed that Mr. Trump won the popular vote, Google made money because it arrived as an advertisement keyed to searches about the election results.