One of the problems of truth being censored for a really long time is that people lose the ability to intuit what truth might be, and therefore begin to swallow whatever they're fed. I think that's something that the Chinese have learned very well. They've even managed to persuade quite large segments of the population that the martyrs of Tiananmen were actually an anti-national element. People don't view them as heroes, they see them as troublemakers. There you have a combination of censorship of truth creating a new truth, which is the lie, but it's not seen as such.
