While at school I had endless debates with more pro-US-government students, and it was mind-boggling to see how they refused to acknowledge even CIA-operations that the CIA itself has declassified, or tried to dismiss interviews with past CIA directors.

The ability to just flat out deny these things when they don't fit the narrative of the the government (any government) that people want to believe in.

If people think a given government is good, a large portion of them will not take evidence of said government doing something bad and revise their opinion of the government - they'll write off the evidence instead.

Even when said evidence comes from the very same government.