Media bias has existed since the dawn of the printing press. Read the book "The New Republic" written in 1883, there's an entire chapter devoted to that. Here's an excerpt...
"The power of the press is everywhere acknowledged. If devoted to the interests and welfare of the hole, its power for good is immeasurable; and no less the evil if given to the service of corporate power and associated capital in the hands of the few.
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In addition to this, the press caters to selfish interests, and is effectually controlled in the interests of the oligarchy, to monopolize the intelligence of the country and shape it so as to control public sentiment. We offer the following, copied from an Eastern paper, which will explain itself:
The real truth concerning the capitalistic press of America was uttered by a prominent New York journalist at a press dinner a short time since. The reunion on that occasion was of men who write and do the real work on the papers - the drudges. When the hackneyed and ridiculous toast, 'The Independent Press,' was proposed, the journalist referred to, being called on to respond, said he did not wish to do so, but the company insisted upon it with loud acclamations. He finally arose and said:
''There is no such a thing in America as an independent press, unless it is out in country towns, You are all slaves. You know it, and I know it. There is not one of you who dares to express an honest opinion. If you expressed it, you would know beforehand that it would never appear in print. I am paid $150 for keeping honest opinions out of the paper I am connected with. Others of you are paid similar salaries for doing similar things. If I should allow honest opinions to be printed in one issue of my paper, I would be like Othello before twenty-four hours: my occupation would be gone."
"The man who would be so foolish as to write honest opinions would be out on the street hunting for another job. The business of a New York journalist is to distort the truth, to lie outright, to pervert, to villify, to fawn at the feet of Mammon, and to sell his country and his race for his daily bread, or for what is about the same his salary. You know this, and I know it; and what foolery to be toasting an ''Independent Press"!
We are the tools and vassals of rich men behind the scenes... Our time, our talents, our lives, our possibilities, are all the property of other men, we are intellectual prostitutes."