In the 1950s Iran democratically elected a government. That government decided to nationalize their oil fields, meaning they decided to kick British Petroleum out of their country and take over the oil fields for themselves. The CIA and England joined forces and ousted the democratically elected government so that British Petroleum could get their oil fields back. They then installed their own puppet ruler, the Shah of Iran.
The Shah of Iran was an a-hole who nobody liked and had lavish parties while everybody else suffered. Students in Iran stormed the U.S. Embassy and demanded the Shah be extradited. Carter talked to them for a year and tried to negotiate the hostages release from the students. Reagan then took over and forcefully freed the hostages with military helicopters and the U.S. Military.
The students were fighting for their rights after being wronged by a western puppet ruler. Carter got a bad rap for not being able to free the hostages. Reagan gets credit for being tough and not standing for any resistance. The students were standing up for their rights.
The next chapter in this history is that the Islamic revolution came about which expelled the Shah of Iran and now we are dealing with the aftermath which is a hardline Islamic government in Iran which wants nuclear weapons is the general theory. This is payback for what the United States and Britain and the corrupt corporations did to Iran starting in the 1950s.