Not long after Donald Trump’s surprising presidential victory, an article published in the Swiss weekly Das Magazin, and reprinted online in English by Vice, began churning through the Internet. While pundits were dissecting the collapse of Hillary Clinton’s campaign, the journalists for Das Magazin, Hannes Grassegger and Mikael Krogerus, pointed to an entirely different explanation—the work of Cambridge Analytica, a data science firm created by a British company with deep ties to the British and American defense industries.

According to Grassegger and Krogerus, Cambridge Analytica had used psychological data culled from Facebook, paired with vast amounts of consumer information purchased from data-mining companies, to develop algorithms that were supposedly able to identify the psychological makeup of every voter in the American electorate. The company then developed political messages tailored to appeal to the emotions of each one. As the New York Times reporters Nicholas Confessore and Danny Hakim described it:

A voter deemed neurotic might be shown a gun-rights commercial featuring burglars breaking into a home, rather than a defense of the Second Amendment; political ads warning of the dangers posed by the Islamic State could be targeted directly at voters prone to anxiety….

Even more troubling was the underhanded way in which Cambridge Analytica appeared to have obtained its information. Using an Amazon site called Mechanical Turk, the company paid one hundred thousand people in the United States a dollar or two to fill out an online survey. But in order to receive payment, those people were also required to download an app that gave Cambridge Analytica access to the profiles of their unwitting Facebook friends. These profiles included their Facebook “likes” and their own contact lists.

According to the investigative reporter Mattathias Schwartz, writing in The Intercept, a further 185,000 people were recruited from an unnamed data company, to gain access to another 30 million Facebook profiles. Again, none of these 30 million people knew their data were being harvested and analyzed for the benefit of an American political campaign.

Facebook did turn out to be essential to Trump’s victory, but not in the way Grassegger, Krogerus, and Schwartz suggest. Though there is little doubt that Cambridge Analytica exploited members of the social network, Facebook’s real influence came from the campaign’s strategic and perfectly legal use of Facebook’s suite of marketing tools. (It should be noted that internal Facebook documents leaked in early May show that Facebook itself has been mining users’ emotional states and sharing that information with advertisers.)

After the initial alarm that an obscure data firm might have wormed its way into the American psyche deeply enough to deliver the election to Trump, critics began to question what Alexander Nix, the head of Cambridge Analytica, called the firm’s “secret sauce,” the algorithms it used to predict a voter’s psychological profile, what is known as “psychographics.” Confessore and Hakim’s article about the firm, which appeared on the front page…