Steve Kornacki has an excellent column in PolitickerNY about why President Obama is right not to utter red-meat rhetoric concerning events in Iran, and why John McCain and some of his Republican colleagues are wrong
The question isn't whether having the CIA, back in 1953 and largely at the behest of the British, put into action a coup d'état against the premiership of Mohammed Mossadegh was a good thing (I believe it wasn't), or whether Mossadegh, had he not been deposed, would have brought Iran into alliance with the Soviet Union (I think he would have gladly taken aid, military and otherwise, from the U.S.S.R., and would have proclaimed Iran "non-aligned", which, in practice, would have meant voting with the Sovs in the U.N. most of the time; in other words, much like India in the 1950s and '60s). It isn't even whether he would, bribed sufficiently, have allowed the Russkies their wet dream of a warm water naval port, right on the Straits of Hormuz.
No matter what geopolitical horror scenes you can imagine, retrospectively, from not overthrowing Mossadegh, the present reality is that even those Iranians who are protesting against the election results remember this episode of Western interference in their politics ruefully. So, right or wrong, the U.S. is constrained in the appeals it can now make. Appeals to basic human rights concerns; yes. Appeals to "democracy" (whether or not you dispute Mossadegh's status, at the time he was deposed, as "democratically elected") may ring hollow, and will, no doubt, be used by those in power to discredit the source by recalling the anti-Mossadegh coup.
Image courtesy of Tehran24.