I mean, propaganda is a pretty strong tool and can easily be used to mold someone's brain at a young age. So how did the Revolutions of 1989 happen? Wouldn't everyone just be a good little communist?
I asked a similar question 3 years ago, you may be interested in the answers by u/kaisermatias, u/ruber_r, u/Emnel and u/Fucho. Not to discourage other answers of course, there's always more to say.