Are you saying Evo Morales was a dictator? Because a lot of US media might imply that, but few major papers ever said it outright because they usually try to at least pretend not to be full of shit. In reality he was a very popular democratically elected leader, and organizations established and funded by the US (and its business interests) played a critical role in the coup d’etat against him. It is not a conspiracy, there is a straight line from US influence to the coup, even if it was ultimately carried by local Bolivian business interests. In fact understand the relationship between American foreign policy objectives, multinational corporations, and local business interests is key to understanding modern neocolonialism as a whole.
On paper it acts independently, but it’s headquartered in Washington DC, and according to Wikipedia “In 2018 the [OAS]General Secretariat’s budget was $85 million of which the US contributed $50 million.” And of course, the US has always considered South America to be its “backyard” and has a long history of doing this kind of thing