I wasn’t in Tehran but I was in the Fulda Gap guarding West Germany during that time. Many of us in the military were very interested and concerned about what was happening and what it might mean to us because of East Germany and Russia.
Over the years, I always put responsibility on Carter but few would take me seriously, claiming I made events too political and anti Democrats.
The Shah was meeting with our Ambassador, Bill Sullivan, at 3 AM in the mornings trying to make a decision. He felt betrayed by us and rightfully so. Khomeini hijacked the Revolution and started killing off the opposition.
Iran was a very liberal place when I first arrived in July 1977. You could buy Playboy at the newsstand. Women were in Western dress; alcohol was served in restaurants and bars; Iran had more students in US universities than any other country, over 50,000 and there were more women in the Iranian Parliament than in the US Congress. Israel had a trade mission in Tehran. That all changed overnight when Khomeini returned from exile in France.
In terms of numbers, Tehran was our largest Embassy in the world with more than a 1,000 US employees including the military mission. We lost significant intelligence assets monitoring the Soviet nuclear program across the Caspian. It was a huge loss to the intelligence communityy,
The Shah was corrupt, but we and the Iranian people would be far better off today if the Iranian Revolution had not succeeded.