Sorry if it's too difficult to compare the two situations. This is a question that comes to mind when I hear people talking about how inept the CIA was when dealing with Cuba. I've heard they tried to assassinate Castro many times but never succeeded. It would seem easier to influence Cuba since they're so close to the US, whereas Iran is on the other side of the world.
I'm wondering how big of a role the CIA played in the Iranian coup. Did they take advantage of a situation that was brewing, or were they the masterminds behind the whole thing?
You have a very good question. There are historians who have discussed how big of a role the CIA has played. In my opinion CIA is making a mountain out of a molehill and their role is greatly overplayed, especially on reddit. Problem is that people here haven't read anything else than the relevant Wikipedia pages. The Iranian people weren't too happy about Mossadegh back then because of his dictatorial tendencies, his attempt to overthrow the Shah, the economical state of country, jailing of political opponents and refusal to step down according to the constitution. Additionally, some have questioned the documents and have said the CIA has lied in it.
Check out this link: http://www.foreignaffairs.com/articles/141527/ray-takeyh/what-really-happened-in-iran
This is also interesting: http://www.newrepublic.com/article/world/the-great-satan-myth
None of this is to defend America’s role in the coup. But it was hardly the only or even the decisive factor in his fall. Indeed, in the most obvious instance of its meddling in Iranian history, the United States actually meddled on the side of the very religious establishment that now complains so bitterly about the Great Satan.