The 1953 coup was ugly realpolitik, but the Islamic Republic's hostility began in 1979 (hostage crisis, embassy takeover, fatwas against the West). Iran has been the initiator of most modern conflict.
you seem to have all the data but failing to sort them out to see the direct causal link between the point of origin and the current situation.
also I would argue that we should not confuse Iran and the islamists ruling the country. as a reminder the Iranian people suffered thousands if not tens of thousands death recently during violent repression of social unrest. so it seems the Iranian people may disagree with the choices of the people in power. at least until the US joined the israel led war crimes against Iran.
The hostility began in 1953 - too many Iranians hated shah and seen monarchy as oppressors put in by CIA. Even anti islamist Iranians were writing about it. And yes, monarchy was a vialent dictatorship.
Like yes, goverment put in by america wont be hostile to america. But its opponents will blame america for that goverment, because well, they are to blamr. And also, once it fails, all the suppressed anger goes out. And some more, because now america is well positioned to be generic scapegoat even for stuff it had not done.
So you don't think 1953 had anything to do with 1979? It just kind of happened out of the blue?