Of course, the CIA and US Government does actually do propaganda campaigns. Whether via things like the Voice Of America radio station. Or like
Domestic Anti-Communist stuff:
Operation Mockingbird bird: https://en.wikipedia.org/wiki/Operation_Mockingbird,
The Crusade for Cultural Freedom.
https://en.wikipedia.org/wiki/Crusade_for_Freedom
The Congress for Cultural Freedom. https://en.wikipedia.org/wiki/Congress_for_Cultural_Freedom
The Red Scare. https://en.wikipedia.org/wiki/Red_Scare
More general fuckery:
Lavender Scare. https://en.wikipedia.org/wiki/Lavender_scare
The suppression of the PRISM information program. https://en.wikipedia.org/wiki/PRISM
Suppression of wartime massacres: https://en.wikipedia.org/wiki/Mukaradeeb_wedding_party_massacre
The assassin of Fred Hampton (American communist)
https://en.wikipedia.org/wiki/Assassination_of_Fred_Hampton
The killing of MLK (American Socialist).
https://en.wikipedia.org/wiki/Assassination_of_Martin_Luther_King_Jr.
And that's just a small portion of the US government propaganda campaigns they've run ON AMERICAN CITIZENS AND CULTURE. Not including things like the outlawing of Anarchism, or whatever the hell people like Allen Dulles and George Bush Senior were up to...
...and all of this is before even asking about overseas propaganda campaigns.
So yes, the CIA has definitely been heavily involved in curbing American opinions, and massively suppressing support for Communism and Socialism in America.
American Free speech - but only to an extent, after that you'll have to deal with government interference.