There's quite a difference between social media interjecting its opinion into your private, personal conversations and whatever the clergy at your local church back in the 90s would have said. They would not have even had visibility into say, what you might be talking about at the local pub or hanging out with your neighbors. A local newspaper might pitch a story, but editorials were clearly labeled and there were often competing newspapers in most towns. Statistically, police brutality isn't a problem and far more people suffer from the effects of too little policing than not (see murder rate in Chicago or Juarez). In this era, we suffer from magnification and amplification of the marginal. A thing that does not occur very often, statistically, can get blown completely out of proportion. The power of social media is the power of propaganda. Propaganda has been used throughout history to start wars, revolutions, religious battles, etc. It has the ability to shape the perception of reality in a way that has heretofore been unthinkable. Facebook alone has an audience and reach that no TV channel or newspaper has ever had. Quantity has a quality all its own.