I'm so dumb it took a long time for me to realize that Walter Cronkite, Tom Brokaw, Huntley - Brinkley, Dan Rather, Bob Schieffer, et al, were die hard Democrats. But I was a Democrat back then too, and it wasn't obvious. As Andrew Malcolm said:
At times I’ve described media bias to intelligent liberal friends. They don’t see it. They can’t see it. It’s like asking a fish what water tastes like. That environment is all it’s ever known.
When you're riding a bike or jogging with the wind at your back you don't notice it until you turn against it. That's what it's like when you become conservative. All of a sudden the liberal media is a strong wind in your face.
Apparently, Donald Trump has the wind in his face and the sand blowing in his eyes now. He didn't notice it when he was a Democrat. Now that he's a Republican he is experiencing first hand what conservatives have seen for years.
All his predecessors who earned the Republican nomination tried to get along with the msm. However, we are learning that Trump is attempting to go to war with the media. He's unlikely to change their minds, but that's not the point. Whether his is a good or bad strategy is something we'll learn in the next few months.