yeah, my understanding is that mccarthy was essentially a useful idiot - that the fbi fed him a lot of psy-ops, and that he was essentially a foot soldier for the secret service.
and, i've said largely the same thing about contemporary actors, that are out there right now pushing what is essentially just propaganda about russia, in order to take a loose canon president down a notch.
https://theanalysis.news/interviews/demagogues-from-mccarthy-to-trump/