Facebook’s surveillance and spying operation turned over data to  psychologists to craft targeted, specific propaganda messages designed to hook targets into adopting someone else’s agenda – literally, Facebook is a platform for propaganda and mind control, using well known, specific methods to manipulate people.

Mr. Wylie was interested in using inherent psychological traits to affect voters’ behavior and had assembled a team of psychologists and data scientists, some of them affiliated with Cambridge University.The group experimented abroad, including in the Caribbean and Africa, where privacy rules were lax or nonexistent and politicians employing SCL were happy to provide government-held data, former employees said.
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Building psychographic profiles on a national scale required data the company could not gather without huge expense. Traditional analytics firms used voting records and consumer purchase histories to try to predict political beliefs and voting behavior.

But those kinds of records were useless for figuring out whether a particular voter was, say, a neurotic introvert, a religious extrovert, a fair-minded liberal or a fan of the occult. Those were among the psychological traits the firm claimed would provide a uniquely powerful means of designing political messages.

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He ultimately provided over 50 million raw profiles to the firm, Mr. Wylie said, a number confirmed by a company email and a former colleague. Of those, roughly 30 million — a number previously reported by The Intercept — contained enough information, including places of residence, that the company could match users to other records and build psychographic profiles. Only about 270,000 users — those who participated in the survey — had consented to having their data harvested.

Source: How Trump Consultants Exploited the Facebook Data of Millions – The New York Times
This is vastly worse than a Russian business operation buying $44,000 worth of Facebook ads.