The change happened during Vietnam and was complete by the resignation of Nixon.
The televised media felt empowered to promote an agenda. As they were overwhelmingly liberal, the approach was to repeat a message until we poor dweebs caught on.
What we do not know, MNJohnnie, is how much was falsified back then.
Perhaps but the big difference was they at least made an effort to present both sides. Even if they were clearly slanted against one point of view, it was at least out there.
NOW all you hear is ONE side. That of the "Journalists" personal political views.
Here is another example.
How is it that the Chief political reporter for AP, (Associated Press virtually the only source for most Broadcast and Publish "News" in the USA), Jennifer Loven is allowed to keep her job despite being married to a former Clintonite and Democrat National Committee big wig?
That sort of clear conflict of interest would be obvious grounds for dismissal or reassignment to other duties in any other industry. In the "News Media" for a "Journalists" that standard operating procedure.
What we do not know, MNJohnnie, is how much was falsified back then.
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There is more instant criticism of media output these days, but I am a witness to the bias in reporting all the way back to the post-WW II years. In the early days of TV, I attended meetings and then saw how the meetings were portrayed by selective camera angles, and selective choice of soundbites on the evening news, to sell to the viewers what the TV crews and producers wanted people to see and hear, not a faithful representation of the contents of the meeting or lecture.