U.S.-Iran Relations: A Timeline

1953: The CIA assists in coup

U.S. and British intelligence agencies laid the groundwork for a coup in Iran that would oust the country’s prime minister, Mohammad Mosaddegh, and return to power a monarchy that was friendly to the West, in the form of Mohammad Reza Shah Pahlavi. The act that prompted the coup was Mosaddegh’s nationalization of the country’s oil production, which had previously been controlled by the British. In the aftermath the U.S. and U.K. strong-armed the shah into giving U.S., British, and French oil companies an ownership stake in Iran’s oil production for 25 years. It would not be the last time oil played a key role in Western relations with Iran. (The CIA, which had long denied playing a role in the toppling of the Mosaddegh government, admitted its involvement in 2013.)

• Read more: Who was the Shah of Iran?

1950s–70s: Largely unfettered U.S. support

While the shah proved to be deeply unpopular among his people for his autocratic rule, American presidents feted him. In 1957, under an Eisenhower administration program called “Atoms for Peace,” Iran received nuclear education and technology, which laid the foundation for its nuclear program. In 1972 U.S. Pres. Richard Nixon appeared in Tehran as part of a state visit, during which the American president and the Iranian monarch waved to crowds from an open-top limousine. Domestically, the shah’s program for modernizing his country—dubbed the White Revolution—was economically successful but culturally deeply divisive.

• Read more: Why did the White Revolution fail?

1979: Revolution comes to Iran

By the late 1970s the Iranian people had had enough of the shah. Their unrest was encouraged by the exiled Iranian Muslim cleric Ruhollah Khomeini, who orchestrated a revolution from a Paris suburb through recorded messages delivered to the Iranian masses. The shah fled the country in January 1979, and on February 1 Khomeini returned triumphant to Iran and was proclaimed the leader of the Iranian Revolution. He would lead Iran until his death in 1989, during which time he would dub the United States “the Great Satan.”

• Read more: The anatomy of the Iranian Revolution

1979–81: The Iran hostage crisis

In October 1979 the U.S. government allowed the shah to enter the country for medical treatment. Iranian protesters seethed. On November 4, 1979, some 3,000 Iranian college students stormed the U.S. embassy in Tehran and took 66 Americans hostage. Some would be freed, but for the remaining 52 hostages, the ordeal would last 444 days, making Iran front of mind for the U.S. public in a way it had never been before. Americans tied yellow ribbons everywhere as a sign of unity and commitment to bringing the hostages home. ABC anchor Ted Koppel updated Americans nightly on developments, ending each broadcast with a count of how many days the hostages had been held.

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The hostages would eventually be freed on January 20, 1981, just moments after Ronald Reagan was sworn in as president. The crisis had probably cost Jimmy Carter reelection, and a badly botched rescue mission in April 1980 cost eight American service members their lives when a helicopter and plane collided.

• Read more: A history of American civilians held captive

1980–88: Iran-Iraq War

Iraq invaded Iran in a war that pitted Iraq’s Saddam Hussein against Iran’s Ruhollah Khomeini. It would also raise the profile of Iran’s hard-line president, Ali Khamenei, who would become the country’s supreme leader after the death of Khomeini in 1989. It was a title he would hold until his own death, caused by American and Israeli attacks in 2026. The U.S. supported Iraq in the brutal and bloody conflict, during which Iraq used chemical weapons on the Iranians. It ended when Iran, which by some estimates had lost one million citizens, agreed to a United Nations-brokered deal in July 1988. The shooting down of an Iranian passenger jet, with 290 people aboard, by missiles fired from the USS Vincennes earlier that month was seen as hastening Iran’s acceptance of the ceasefire deal. The American forces mistook the plane for a fighter jet, and the U.S. characterized the downing of the plane over the Strait of Hormuz as “a tragic and regrettable accident.” In Iran it was widely believed that the U.S. attack had been deliberate, and Iranian authorities worried that it indicated the United States was planning to join forces with Iraq.

• Read more: The rise of Ali Khamenei, the man who would rule Iran for decades

1983: Beirut barracks bombings

In one of the defining moments of the 1980s, 241 American marines and sailors were killed when their barracks in Beirut were blown up by truck bombs. Another 58 French soldiers were killed in a second attack. Islamic Jihad, believed to be affiliated with Hezbollah, a group of Lebanese militants backed by Iran, took credit for the attack. The year after the attacks, the U.S. State Department declared Iran a “state sponsor of terrorism.”

• Read more: How the bombings drove Americans out of Lebanon

1985–87: Iran-Contra Affair

Despite a U.S. arms embargo that prohibited sales of weapons to Iran, Reagan administration officials hatched a plan to sell arms to Iran to secure the release of Americans held by the Iran-backed militant group Hezbollah. U.S. officials then used the proceeds from the sale of the weapons to fund contra rebels in Nicaragua after Congress cut off funding. The scandal consumed much of Ronald Reagan’s second term. Hezbollah killed two of the hostages and released the rest over the course of several years.

• Read more: How exactly did Iran and Nicaragua wind up in the same scandal?

1990s: Economic sanctions

During the administrations of George H.W. Bush and Bill Clinton, the U.S. government tried to curb Iranian aggression through a series of economic sanctions. Some of the most far-reaching sanctions were outlined in the Iran and Libya Sanctions Act of 1996, which expanded an existing U.S. embargo on the import of Iranian petroleum products to include extensive bans on investment by both U.S. and non-U.S. companies in Iran. These sanctions also prohibited foreign speculation in Iranian petroleum development, the export of high technology to Iran, and the import of a wide variety of Iranian products into the United States. Ultimately, the sanctions had little impact on the actions of the Iranian government.

• Read more: Do economic sanctions ever work?

1998–2001: A thaw in relations

During the waning days of the Clinton administration, Secretary of State Madeleine Albright engaged in bridge building with Iran in a variety of ways. In 1998 she met with Iran’s deputy foreign minister, the highest-level meeting between American and Iranian officials in nearly two decades. She also acknowledged that the U.S.’s role in the 1953 coup was a source of ongoing resentment by the Iranian people. After the 9/11 terrorist attacks and the U.S. invasion of Afghanistan, the U.S. and Iran worked together on an agreement to enable displaced Afghan citizens to return home.

• Read more: Who was Madeleine Albright?

2002: “Axis of evil” speech

Whatever tentative olive branches had been exchanged were trampled during Pres. George W. Bush’s 2002 State of the Union address, in which he labeled Iran, Iraq, and North Korea “an axis of evil.” He went on to say, “Iran aggressively pursues these weapons [of mass destruction] and exports terror, while an unelected few repress the Iranian people’s hope for freedom.” Years later, in 2006, in the first direct communication between Iranian and U.S. heads of state since 1979, Iranian Pres. Mahmoud Ahmadinejad wrote Bush a stunning approximately 18-page letter asking for an easing of nuclear tensions while refusing to stop uranium enrichment, which he said was for energy and not war.

• Read more: The text of Ahmadinejad’s letter to Bush

2013–18: The Iran nuclear deal that was, until it wasn’t

In 2013 Pres. Barack Obama called Iran’s newly elected president, Hassan Rouhani, to discuss a potential nuclear deal. The call was the most direct contact between the leaders of the two countries since 1979. It ultimately led in 2015 to the Joint Comprehensive Plan of Action (JCPOA), an agreement involving the U.S., Iran, China, France, the U.K., Germany, Russia, and the European Union. In exchange for the easing of some sanctions, Iran agreed to dismantle a nuclear reactor, limit uranium enrichment for at least 15 years, and have its compliance monitored. The plan faced resistance from members of Congress—Democrats and Republicans alike—who argued that it would allow Iran too much power in the region. In 2018 Pres. Donald Trump pulled the U.S. out of the JCPOA. In 2019 Trump declared the Iranian Revolutionary Guard Corps a foreign terrorist organization.

• Read more: What did the JCPOA do and not do?

2020: Killing of Soleimani

Qassem Soleimani was an Iranian general seen as one of the most powerful leaders in the country and head of the elite Quds Force, which handles military operations outside Iran. He was assassinated in a U.S. drone strike at the Baghdad International Airport. The killing, which had been considered but rejected by both the George W. Bush and Obama administrations, was seen as highly provocative, but Trump denied that it was an act of war against Iran, saying, “I don’t think that would be a good idea for Iran. It wouldn’t last very long.…I want to have peace. I like peace.” In the aftermath of Soleimani’s assassination, the U.S. alleged that Iran retaliated by attempting to kill former national security adviser John Bolton.

• Read more: What is the Quds Force?

2022: Woman, Life, Freedom protests

The 2020 election of Joe Biden led to tentative efforts to restore the JCPOA, but any progress made was squashed by the 2021 election of hardline cleric Ebrahim Raisi as president of Iran. By mid-2022, while on a visit to Israel, Biden vowed that the U.S. would prevent Iran from achieving nuclear weapons. In the fall of 2022 thousands of women took to the streets of Iran to protest the death of Jina Mahsa Amini, who died while in police custody. Amini was arrested for allegedly not properly wearing a hijab. Protesters carried signs and chanted “Zan, Zendegī, Āzādī,” which translates to “Woman, Life, Freedom!” Biden spoke about Amini’s death and the subsequent protests, saying, “I want you to know that we stand with the citizens, the brave women of Iran.”

• Read more: Who was Jina Mahsa Amini?

2025: U.S. and Israel strike Iranian nuclear sites

After winning the 2024 presidential election, Donald Trump began his second term with threats and offers to talk to Iran. He warned that Iran must stop supporting its proxies, the Houthis and Hezbollah, in their campaign against Israel. Conciliation came in the form of talks between U.S. special envoy Steve Witkoff and Iran’s foreign minister. The quid pro quo of an end to Tehran’s nuclear program in exchange for the easing of sanctions remained the endgame. But in June 2025 Israel launched attacks on Iran that targeted nuclear sites and killed top military leaders. A week later, the U.S. launched its own attacks, marking the first time that the U.S. had directly struck Iranian soil. In a speech to the country, Trump announced:

Tonight, I can report to the world that the strikes were a spectacular military success. Iran’s key nuclear enrichment facilities have been completely and totally obliterated. Iran, the bully of the Middle East, must now make peace. If they do not, future attacks would be far greater and a lot easier.

• Read more: How did tensions escalate between Israel and Iran in 2025?

2026: U.S. and Israel attack Iran, the supreme leader is killed, and a quagmire ensues

In late December 2025 and January 2026, hundreds of thousands of Iranians took to the streets to protest the Iranian regime and the economic crisis gripping the country. By some estimates the government killed more than 30,000 of those protesters. Trump offered encouragement to protesters, and there was speculation that the Iranian government could collapse. Then, on February 28, the U.S. and Israel launched what Trump called a “massive” operation in Iran, code-named Epic Fury, that struck scores of sites around the country and killed Supreme Leader Ali Khamenei, who had led the country since 1989. Trump warned Americans that “the lives of courageous American heroes may be lost, and we may have casualties. That often happens in war.” Iran retaliated, striking Israel and other U.S. allies in the region, including Bahrain, Qatar, Kuwait, and the United Arab Emirates. In the immediate aftermath of the attacks, global oil delivery was threatened. U.S. justifications for the attacks included the need to change the Iranian government so that the country’s people could seize control, an imminent threat posed by Iran’s nuclear program, and the knowledge that Iran planned to strike again.

Over the course of spring and early summer, the conflict transitioned from high-intensity air battles to a seeming deadlock between the two sides that resulted in the blockade of the Strait of Hormuz, triggering a global energy crisis. With the help of Pakistan, Iran and the U.S. entered into a ceasefire in April. That agreement, however, didn’t stop the conflict from escalating into Lebanon.

In early March Trump said that the war would be over in “four to five weeks,” and he subsequently claimed victory only to threaten renewed attacks. On June 11 Trump called off previously announced plans for “VERY HARD” strikes on Iran, saying that a breakthrough had been made and an agreement reached “in both concept and great detail” by the United States, Israel, and other affected countries. That was followed by an announcement on June 14 that an understanding had been reached to end hostilities and open the Strait of Hormuz, end the U.S. blockade of Iran’s ports. It does not address Iran’s nuclear program and Israel seems opposed to any elements that limit its ability to continue to act in Lebanon.

The conflict—which was very unpopular, according to polling in the United States, and which sent gas and diesel prices soaring—has drawn comparisons to the 444-day hostage crisis. Scholars noted that during that ordeal, the Carter administration repeatedly thought that a release deal was imminent only to have hopes dashed by an Iranian regime determined to outlast the Americans.

• Read more: What does the memorandum of understanding actually say?