In the US the primary story we hear about Iran is that it is run by genocidal nuclear-weapon wielding madmen who presumably came to power on the back of the death of millions of innocents. Optional flourishes may include claims about how these leaders do (or do not) represent the evil inherent in Islam and/or the evil inherent in the Iranian people.
If you’d prefer a rather more nuanced view, you could not do better than Richard Bulliet’s speech at Columbia on April 21, 2008, Three Decades of the Islamic Republic of Iran@. Bulliet is interested in comparing the causes, but more so the progress, of the Iranian revolution to the standard pattern of other political revolutions in history (eg France or Russia) — who are the disaffected groups, how do they work together to bring about change, and how do they then, via negotiation or force, construct the new political order. He has, for example, very interesting things to say about the place of the military in Iranian politics, a statement I don’t believe I’ve ever heard a single useful comment upon from the US media.