You don't have to jail people if they consent to being their own mental jailors. You can easily keep them ignorant by simply feeding them a lot of false information. Americans (in a general sense) are famous all around the world for their ignorance of what the world is like outside their own borders.

The so-called "free press" in North America is mostly owned by a few conglomerates, major corporations, and they control the viewpoints expressed in 98% of what goes out in print. This results in a population that is spoon fed nonsense from the day they are born till the day they die, and they believe it, of course.

There are numerous societies which are freer and more open-minded than the USA is right now. Iran is not one of them, needless to say. ;-) But I doubt that Iranians are stupid, and I think you might find a good many of them more aware of certain realities than you think. Third World people are often more realistic about what's going on internationally than their spoon-fed, fat, coddled, stupefied counterparts in North America are. Why? Because they deal with the more unpleasant consequences of what's going on directly, rather than spending their evenings watching "Survivor" and speculating about the death of Anna Nicole Smith.