Operation Ajax (1953) (officially TP-AJAX) was a covert operation by the United Kingdom and the United States to remove the nationalist[1] cabinet of Iranian Prime Minister Mohammed Mossadegh from power, to support the Pahlavi dynasty and consolidate the power of Shah Mohammed Reza Pahlavi. The idea of overthrowing Mossadegh was conceived by the British. They originally asked President Truman for assistance, but he refused. When Eisenhower became president in 1953, the British proposed the idea once again, and this time, the Americans agreed to help.

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For the U.S., an important factor to consider was Iran’s border with the Soviet Union. A pro-American Iran under the Shah would give the U.S. a double strategic advantage in the ensuing Cold War, as a NATO alliance was already in effect with the government of Turkey, also bordering the USSR. In planning the operation, the CIA organized a guerrilla force in case the communist Tudeh Party seized power as a result of the chaos created by Operation Ajax. According to formerly “Top Secret” documents released by the National Security Archive, Undersecretary of State Walter Bedell Smith reported that the CIA had reached an agreement with Qashqai tribal leaders in southern Iran to establish a clandestine safe haven from which U.S.-funded guerrillas and intelligence agents could operate. Operation Ajax was the first time the Central Intelligence Agency was involved in a plot to overthrow a democratically-elected government. The success of this operation, and its relatively low cost, encouraged the CIA to successfully carry out a similar operation in Guatemala a year later.

In 1977, following human rights pressure from U.S. President Jimmy Carter (who threatened to cut arms shipments), more than 300 political prisoners were released, censorship was relaxed, and the court system reformed. This loosening of restrictions led to more campaigns from the opposition, where writers campaigned for freedom of thought, and people began to demonstrate. Also, the policy of land reform which the Shah implemented, and had also been caused by pressure from the Carter administration, infuriated the mullahs (who declared a holy war against the Shah), and contributed to the Shah's problems. This early opposition was led by Mehdi Bazargan and his Freedom Movement of Iran. It was a liberal, secularist group that was closely linked to Massadegh's National Front. This group saw significant support in Iran and abroad in the West. More revolutionary was Ali Shariati, a popular and well respected teacher and philosopher who sought to achieve social justice and democracy through a modern interpretation of Islam. Prior to the rise of Khomeini, Shariati was the most prominent and outspoken leader of the opposition. His murder in London in 1977 greatly inflamed tensions. As a result, Khomeini eventually became the primary figurehead of the Revolution. The clergy were divided, some allying with the liberal secularists, and others with the Marxists and Communists. Khomeini, who was in exile in Iraq, led a small faction that advocated the overthrow of the regime and the creation of a theocratic state. In late 1977, Khomeini's son Mostafa Khomeini was found dead of unknown reasons; Khomeini himself blamed the Shah's secret police. The various anti-establishment groups operated from outside Iran, mostly in London, Paris, Iraq, and Turkey. Speeches by the leaders of these groups were placed on audio cassettes to be smuggled into Iran. The speeches could then be listened to by the largely illiterate population.

January 20, 2002, U.S. State of the Union

[Our goal] is to prevent regimes that sponsor terror from threatening America or our friends and allies with weapons of mass destruction. Some of these regimes have been pretty quiet since September the 11th. But we know their true nature. North Korea is a regime arming with missiles and weapons of mass destruction, while starving its citizens. Iran aggressively pursues these weapons and exports terror, while an unelected few repress the Iranian people's hope for freedom. Iraq continues to flaunt its hostility toward America and to support terror. The Iraqi regime has plotted to develop anthrax, and nerve gas, and nuclear weapons for over a decade. This is a regime that has already used poison gas to murder thousands of its own citizens—leaving the bodies of mothers huddled over their dead children. This is a regime that agreed to international inspections—then kicked out the inspectors. This is a regime that has something to hide from the civilized world. States like these, and their terrorist allies, constitute an axis of evil, arming to threaten the peace of the world. By seeking weapons of mass destruction, these regimes pose a grave and growing danger. They could provide these arms to terrorists, giving them the means to match their hatred. They could attack our allies or attempt to blackmail the United States. In any of these cases, the price of indifference would be catastrophic.

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The above was from Wikipedia and, as always, the specifics are subject to debate. However, I think the broad outline of the role of the United States and the UK in Iran should be clear:

Happy anniversary, U.S. imperialism.

Here is more information on the democratic revolutionary figure Ali Shariati and contemporary intellectual Abdolkarim Soroush. If someone can point to sources for the century-long history of Iranian feminism or examples thereof in the comments, it would be greatly appreciated.

Peace.