The Wikileaks founder/icon gave an interview to Russia Today where he called the social network "the most appalling spy machine that has ever been invented". Assange believes that Facebook was developed for U.S. intelligence to use. He says when you put your information in to Facebook, you're making life easier for U.S. officials who have free run of all the information there. He says it's not that the network is operated by the government; it's just that the government can easily bring legal and political pressure to bear on Facebook and that it does so very frequently.
These are not crackpot theories, mind you. There's plenty of collaboration between online businesses and law enforcement. Most of it is kept pretty quiet. Whether one sees it as an intrusion of privacy or a concerted effort to round up crooks is open to individual world view.

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