In 2006, a local pollster in Nepal was kidnapped by Maoist rebels while conducting opinion surveys on behalf of the American political strategist Stan Greenberg. The Maoists, who had been waging a long-running insurgency against the government, did not issue their typical ransom demands—money or weapons in exchange for the prisoner. No, they wanted the polling data that Greenberg’s team had collected, evidently to gauge the political climate in the country for themselves. The researchers eventually handed it over. In his book “Alpha Dogs,” the British journalist James Harding cites this story as an example of how the business of political campaigning is being remade, across the globe, by a profusion of fine-grained data about voters and their habits. Where the consultants of the nineteen-sixties and seventies obsessed over how to use television to beam ideal images of their clients into voters’ homes, today’s spinmasters hope that big data will allow them to manipulate voters’ deepest hopes and fears. “What’s the currency of the world now?” one of Greenberg’s partners asks Harding. “It’s not gold, it’s data. It’s the information.”

Twelve years later, the fixation on data as the key to political persuasion has exploded into scandal. For the past several days, the Internet has been enveloped in outrage over Facebook and Cambridge Analytica, the shadowy firm that supposedly helped Donald Trump win the White House. As with the Maoist rebels, this appears to be a tale of data-lust gone bad. In order to fulfill the promises that Cambridge Analytica made to its clients—it claimed to possess cutting-edge “psychographic profiles” that could judge voters’ personalities better than their own friends could—the company had to harvest huge amounts of information. It did this in an ethically suspicious way, by contracting with Aleksandr Kogan, a psychologist at the University of Cambridge, who built an app that collected demographic data on tens of millions of Facebook users, largely without their knowledge. “This was a scam—and a fraud,” Paul Grewal, Facebook’s deputy general counsel, told the Times over the weekend. Kogan has said that he was assured by Cambridge Analytica that the data collection was “perfectly legal and within the limits of the terms of service.”

Despite Facebook’s performance of victimization, it has endured a good deal of blowback and blame. Even before the story broke, Trump’s critics frequently railed at the company for contributing to his victory by failing to rein in fake news and Russian propaganda. To them, the Cambridge Analytica story was another example of Facebook’s inability, or unwillingness, to control its platform, which allowed bad actors to exploit people on behalf of authoritarian populism. Democrats have demanded that Mark Zuckerberg, the C.E.O. of Facebook, testify before Congress. Antonio Tajani, the President of the European Parliament, wants to talk to him, too. “Facebook needs to clarify before the representatives of five hundred million Europeans that personal data is not being used to manipulate democracy,” he said. On Wednesday afternoon, after remaining conspicuously silent since Friday night, Zuckerberg pledged to restrict third-party access to Facebook data in an effort to win back user trust. “We have a responsibility to protect your data, and if we can’t then we don’t deserve to serve you,” he wrote on Facebook.

But, as some have noted, the furor over Cambridge Analytica is complicated by the fact that what the firm did wasn’t unique or all that new. In 2012, Barack Obama’s reëlection campaign used a Facebook app to target users for outreach, giving supporters the option to share their friend lists with the campaign. These efforts, compared with those of Kogan and Cambridge Analytica, were relatively transparent, but users who never gave their consent had their information sucked up anyway. (Facebook has since changed its policies.) As the sociologist Zeynep Tufekci has written, Facebook itself is a giant “surveillance machine”: its business model demands that it gather as much data about its users as possible, then allow advertisers to exploit the information through a system so complex and opaque that misuse is almost guaranteed.

Just because something isn’t new doesn’t mean that it’s not outrageous. It is unquestionably a bad thing that we carry out much of our online lives within a data-mining apparatus that sells influence to the highest bidder. My initial reaction to the Cambridge Analytica scandal, though, was jaded; the feeling came from having seen how often, in the past, major public outcries about online privacy led nowhere. In most cases, after the calls to delete Facebook die down and the sternly worded congressional letters stop being written, things pretty much go back to normal. Too often, privacy scandals boil down to a superficial fix to some specific breach or leak, without addressing how the entire system undermines the possibility of control. What exciting big-data technique will be revealed, six years from now, as a democracy-shattering mind-control tool?

Yet I eventually found reason to be genuinely repulsed by the story. On Monday, the U.K.’s Channel 4 published video footage of an undercover sting operation that it had conducted against Cambridge Analytica. A man working for the channel, posing as a political operative from Sri Lanka, met with the firm’s representatives to discuss hiring them for a campaign. On camera, over three meetings in various swanky hotels around London, C.A.’s employees offer an increasingly sordid account of their methods and capabilities. The most unseemly revelation—and, in the context of the sting, the most ironic—comes when Alexander Nix, Cambridge Analytica’s C.E.O., seems to offer to entrap the client’s political rivals with secretly videotaped bribes and rendezvous with sex workers. (Nix was suspended on Tuesday.)

Like much of the best investigative journalism, the Channel 4 video gives viewers the queasy sense of a rock being overturned and sinister things being exposed to the light. It is difficult to watch the video without becoming at least a little suspicious of the entire business of democracy, given how large a role political consultants such as Nix play in it these days. Perhaps it is naïve to be scandalized by the cravenness of political consultants in the age of Paul Manafort, whose global democratic-perversion tour took him from buffing the image of the Philippine dictator Ferdinand Marcos, in the nineteen-eighties, to running Trump’s campaign, or to fighting a fraud case for allegedly laundering his fees from the Ukrainian kleptocrat Viktor Yanukovych. But there was something shocking about the stark double identity of this posh “Old Etonian,” as all the British papers call Nix, who presented himself as a big-data wizard at marketing events but proposed basic gangsterism to clients in private. And in the same spiffy suit.

Watching the video makes you understand that the ethical difference between outright electoral corruption and psychographics is largely a matter of degree. Both are shortcuts that warp the process into something small and dirty. You don’t need to believe Cambridge Analytica’s own hype about the persuasive power of its methods to worry about how data-obsessed political marketing can undermine democracy. The model of the voter as a bundle of psychological vulnerabilities to be carefully exploited reduces people to mathematical inputs. The big debates about values and policies that campaigns are supposed to facilitate and take part in are replaced by psychographically derived messages targeted to ever-tinier slivers of voters who are deemed by an algorithm to be persuadable. The organization of all of online life by data-mining operations makes this goal seem attainable, while an industry of data scientists and pollsters pitch it as inevitable. Candidates, voters, and pundits, enthralled with the geek’s promise of omniscience, rush to buy in—at least until it’s used by someone they don’t like. Cambridge Analytica is as much a symptom of democracy’s sickness as its cause.