Revealed: Facebook is a massive spying operation that collects information for the specific purpose of propaganda messaging:

Christopher Wylie, who worked to help obtain the data, told Britain’s The Guardian that Cambridge’s entire operation was designed to “exploit” what they knew about people from their profiles and “target their inner demons.”Cambridge Analytica specializes in “psychographic” profiling that allows them to predict the voting likelihoods of individual people based on personality — and Facebook is a treasure trove for information like that.”We exploited Facebook to harvest millions of people’s profiles,” Wylie told the British news outlet. ”
And built models to exploit what we knew about them and target their inner demons. That was the basis that the entire company was built on.”

Source: Cambridge Analytica, firm that helped Trump’s campaign, used 50 million profiles harvested from Facebook – CBS News
The very definition of a propaganda operation. Facebook’s sole business is spying on you and using that to enable propaganda operations to control your mind. Even your innocuous use of “Likes” can be used to create a surprisingly detailed and accurate description of you.