How would things be different if Mousavi had won the election? I know very little about him.
I believe the people know this, but they are so pi**ed at having the election blatantly ripped out of their hands so that even the semblance of democracy was taken away from them that they just exploded.
That happens when you have been ground under the government thumb for 30 years(since 1979, thanks to Carter)and I think it just came to a head, and POW, you have a riot and possible revolution.