The tense negotiations earlier this month that led to the release of five Americans imprisoned in Iran was the latest headline-grabbing chapter in a fraught diplomatic relationship that stretches back to the 1950s.In 1953, the C.I.A. helped to orchestrate a coup that ousted Prime Minister Mohammad Mossadegh, who was viewed as a threat to Western oil interests. Known as Operation Ajax in the U.S. — British intelligence called it Operation Boot — the plot restored Shah Mohammad Reza Pahlavi, a U.S. ally during the Cold War, to power.
C.I.A. backing helped the shah to maintain his grip, and the Carter administration encouraged him to implement reforms. But growing opposition to corruption and the repression of political dissent fueled a 1979 revolution, the overthrow of the shah by Ayatollah Ruhollah Khomeini, and the decline of American influence. Khomeini ran Iran as a theocracy from 1979 until his death in 1989, imposing a conservative dress code that restricted women's rights. The crackdown sparked a protest movement last year after a 22-year-old woman accused of violating the dress code died in the custody of Iran's morality police. That movement has led to demands for an end to the Islamic republic’s rule. In 2013, the C.I.A. finally acknowledged its role in the effort to overthrow Mossadegh. Today, the United States’ meddling 70 years ago continues to shape international relations and diplomacy.“It’s a little bit like two rail lines, they run parallel but they never come together," said Steven Kinzer, a former New York Times correspondent who covered the region. "Until somehow that logjam can be broken, these two countries are going to remain lamentably separated.”