And we know the extent of US involvement in these coups and conflicts because the US declassified the info, becauase all info becomes declassified eventually.
https://en.wikipedia.org/wiki/Limited_hangout
According to Victor Marchetti, a former special assistant to the Deputy Director of the Central Intelligence Agency (CIA), a limited hangout is "spy jargon for a favorite and frequently used gimmick of the clandestine professionals. When their veil of secrecy is shredded and they can no longer rely on a phony cover story to misinform the public, they resort to admitting—sometimes even volunteering—some of the truth while still managing to withhold the key and damaging facts in the case. The public, however, is usually so intrigued by the new information that it never thinks to pursue the matter further."
US declassification falls squarely into this domain. What gets released into the public record is enshrined as "The Truth" and what gets omitted is reserved to the domain of "Conspiracy Theory". Thus a guy like Allen Dulles can sit on the committee that investigates the assassination of the President and author the copy that the CIA was in no way at fault or otherwise involved in the actions of a disgruntled former agent's actions against the Chief Executive who personally fired Dulles three years earlier.
That’s the problem people have with the Chinese government. They can’t even acknowledge reality
The Chinese Communist Party has its own version of Limited Hangout and goes to some length to assert that the riots in Tienanmen were the result of outside agitation, the civilian death toll was minimal, and the reforms that followed succeeded in restoring trust in the national government.
Westerners choose to ignore the official party line and rely on the equally unreliable narrations of participants who were fully opposed to the party, heavily invested in an insurgent opposition, and outspoken in their desire to abolish the CCP and have its leadership executed.
So you end up with a bunch of smug liberals denouncing Chinese state media as controlled, while regurgitating talking points that came straight out of the John Birch Society and the Falun Gong.
It's propaganda all the way down. Nobody is giving you a complete and accurate picture of events. Any serious scholar must reconstruct events by bits and pieces, sifting through the enormous amounts of FUD. And when their work is completed... good luck finding it, because vanishingly few media moguls have an interest in promoting something that is insufficiently sensational.