They do this through the use of money mostly. Those who can “fundraise” the money pull the puppet strings!
This is what is meant by the term “political operators.”
The hegemony of imperialism has it's own built in immune system. The through line is simple - America is exceptional above all. Criticisms can be freely spoken about any facet of the government (and more importantly it's figure heads), but the default assumption must always be American exceptionalism. The framing is both simple enough that staying on message is easy when a pundit is in the hot seat, and banal enough that it can sway masses without much critical thought. But at the same time it is powerful because it is the framing of every conversation and thought. It legitimizes itself by allowing discussion within this frame and calling it "freedom".
I'm not sure the CIA needs to be that involved. The furvor and jingoistic patriotism of America seems to be doing just fine to elect people who will tow the line.