The United States launched strikes against Iran on June 28, drawing renewed attention to the long history of animosity between the two nations. While Iran maintained friendly ties with the U.S. during the Pahlavi dynasty, relations deteriorated sharply after an Islamic government came to power following the monarchy's collapse. The two countries have clashed for decades without finding resolution. The U.S. once labeled Iran part of an "axis of evil," and despite a period of reconciliation under the Obama administration, multiple attacks have occurred since the Trump administration took office.
In the 1920s, U.S.-Iran relations were cordial. The Pahlavi dynasty, established after Reza Khan seized power in a coup, pursued Western-style modernization. The United States, eager to access Middle Eastern oil, actively supported the Pahlavi regime.
However, in the early 1950s, Mohammad Mosaddegh rose to power on a wave of popular support, championing anti-foreign and nationalist sentiments that put him at odds with Washington.
When Mosaddegh nationalized the oil industry and Iran's Communist Party (Tudeh Party)—strengthened by Soviet influence after World War II—gained power, the Eisenhower administration conspired with Britain to orchestrate a coup restoring the monarchy. The restored Pahlavi dynasty adopted a strongly pro-American stance, initiating military-security cooperation with the U.S. in 1959.
Yet discontent grew over the monarchy's authoritarianism, widening wealth inequality, and Westernization that disregarded Islamic traditions. Ayatollah Khomeini, riding this wave of public sentiment, led the 1979 Islamic Revolution and established a theocratic state.
Shortly after, in November 1979, Iranian university students seized the U.S. Embassy in Tehran, further deteriorating bilateral relations.
Following the Islamic Revolution, Shah Mohammad Reza Pahlavi fled abroad and entered the United States. Iran's revolutionary leadership demanded his extradition, which Washington refused. Enraged Iranian students then occupied the U.S. Embassy in Tehran in November 1979, holding 52 American diplomats and staff members hostage.
The American hostages were released on January 20, 1981—444 days later—on Ronald Reagan's inauguration day, following negotiations with Iran. The embassy hostage crisis ultimately led both countries to sever diplomatic ties.
During the Iran-Iraq War that followed from 1980 to 1988, the U.S. provided direct and indirect support to Iraq, Iran's enemy.
In July 1988, the U.S. Navy cruiser USS Vincennes mistakenly identified an Iranian civilian airliner as a military aircraft and shot it down over the Persian Gulf, killing 290 people and pushing relations to a new low.
In August 1996, the U.S. classified Iran and Libya as state sponsors of terrorism and enacted legislation prohibiting investment in their oil and gas development, launching economic sanctions against Iran. In 2002, President George W. Bush designated Iran, along with Iraq and North Korea, as part of an "axis of evil."
The Barack Obama administration, which took office in 2009, sought to improve relations. In 2013, President Obama spoke by phone with Iranian President Hassan Rouhani—the first such contact in 30 years.
The two nations subsequently worked together on resolving nuclear issues, and reconciliation efforts accelerated in 2015, culminating in a dramatic agreement that July. The Iran nuclear deal (JCPOA, Joint Comprehensive Plan of Action) was reached, under which Iran would halt uranium enrichment and other nuclear weapons-related activities in exchange for Western nations, including the U.S., gradually lifting economic sanctions.
However, relations plummeted again when the first Trump administration took office in 2017. In May 2018, the Trump administration withdrew from the Iran nuclear deal and reinstated economic sanctions.
In January 2020, the Trump administration assassinated Qasem Soleimani, commander of the elite Quds Force of Iran's Islamic Revolutionary Guard Corps (IRGC). In June of last year, the U.S. demonstrated its military might once more with "Operation Midnight Hammer," deploying B-2 stealth bombers to destroy three major Iranian nuclear facilities at Fordow, Natanz, and Isfahan.
After successfully capturing and extracting Venezuelan President Nicolás Maduro in a surprise military operation in January of this year, a newly confident United States—having failed to reach agreement in nuclear negotiations—once again played its military intervention card against Iran.