This is what the US does with countries when they won't play ball. Perhaps Iran should've been more grateful when they were freed from the tyranny of Democracy. The US had a lovely dictator picked out just for them.
Iran is not a democracy, candidates at the presidential election in the coming weeks must be approved by a counsel.
The latter doesn't allow liberal candidates, and iranians have lost interest in the coming election because it will keep the Theocracy currently ruling in power.
Also, the supreme leader is at the top of Iran's power structure and is not elected by the iranian population.
The US had no problem with the Shah and have no problem with Saudi Arabia, despite the war in Yemen and the murder of Khashoggi.
The only have a problem if they can't get the oil, ask Mohammad Mosaddegh.
I am not american, and I wish iranians to have the freedom to chose their government. Most of them hate the islamic regime, this is a country with so much potential, ruined by a Theocracy.
Also, the supreme leader is at the top of Iran's power structure and is not elected by the iranian population.