A revolution also isn't easy when you know that the revolutions you could have, would be the ones supported by foreign groups that absolutely don't want your country well. USA on no account will tolerate an Iran which is both free and democratic and at all economically developed, because they don't trust a democratic public to support pro-American policies in the middle east - especially related to Israel and oil. Just like they don't trust that in any of the Arab states.

If you want a democratic Iran, both the current government of Iran and its most powerful enemies will do everything they can to stop you.