It's become a student rite of passage to discuss this.
I'm no expert but my summary of what I've heard is that in the 19th C a group of wealthy, mainly Jewish, bankers drew up "protocols" on how poeple would be deliberately weakened (morally, socially, emotionally etc) so that they & their governments could be controlled.
It could be an "anti-semitic" conspiracy theory. Some point to how the "protocols of the learned elders of Zion" have in many ways come to pass. Others will say that it was predictable that society would go the way it has (the bible and probably other writings also predicts it).
I don't believe people need some sinsiter group of people controlling the media, they will choose what they watch regardless.
Experts are ready to answer your questions