You normally think of propaganda as something that totalitarian leaders use to control their population.
But we have seen a great deal of propaganda in the U.S. in the mainstream media, articles that everybody seems to believe but are not actually true.
This took a quantum leap in 2016 with the Trump Russia story that after many years have been proven fake, together with hundreds of other stories, seemingly made up from nothing.
Most recently we have seen this in the coverage of the Russian invasion of Ukraine. Stories about the brave Ukrainians and the victories by the Ukrainian military forces are almost all hogwash. The fact is that the Ukrainian military is being pasted by the Russians and the terrified Ukrainians are running for their lives.
Here are examples of the truth in the face of propaganda, and then read the meme from Robert Heinlein who wrote this in 1953. I guess humans have not changed that much in the last 70 years.