The US played a key role in the 1953 coup that overthrew Iran's democratically elected Prime Minister Mohammad Mosaddegh and installed the pro-Western Shah Mohammad Reza Pahlavi. The coup was motivated by concerns that Mosaddegh's nationalist policies, including the nationalisation of the Iranian oil industry, would lead Iran to become a satellite of the Soviet Union.
1979: Iranian Revolution and hostage crisis
The 1979 Iranian Revolution saw the overthrow of the Shah and the establishment of the Islamic Republic of Iran. The new regime was deeply hostile to the US, which it saw as a symbol of Western imperialism and exploitation. In November 1979, Iranian students seized the US embassy in Tehran and held 52 American diplomats and citizens hostage for 444 days. The hostage crisis further soured relations between the two countries.
1980-1988: Iran-Iraq War
During the Iran-Iraq War, the US supported Iraq with intelligence, military equipment, and financial assistance. The US also carried out a number of covert operations against Iran, including the Iran-Contra affair, in which the US sold arms to Iran in exchange for the release of American hostages held in Lebanon.
1995: Khobar Towers bombing
In 1995, a truck bomb exploded outside a US military housing complex in Khobar Towers, Saudi Arabia, killing 19 American soldiers. The US accused Iran of being behind the bombing, but Iran denied any involvement.
2002: Axis of Evil speech
In his 2002 State of the Union address, President George W. Bush included Iran in an "axis of evil" along with Iraq and North Korea. The speech further strained relations between the US and Iran.
2003: US invasion of Iraq
The 2003 US invasion of Iraq was seen by many Iranians as a threat to their country's security. Iran feared that the US might invade Iran next, and it began to develop its nuclear program as a deterrent.
2007-2015: Nuclear negotiations
In 2007, the US and other world powers began negotiations with Iran over its nuclear program. After years of negotiations, the parties reached a deal in 2015, known as the Joint Comprehensive Plan of Action (JCPOA). The deal limited Iran's nuclear program in exchange for the lifting of economic sanctions against Iran.
2018: US withdrawal from JCPOA
In 2018, President Donald Trump withdrew the US from the JCPOA and re-imposed sanctions on Iran. The US also launched a "maximum pressure" campaign against Iran, which included military threats, cyber attacks, and economic sanctions.
2019: Escalation of tensions
In 2019, tensions between the US and Iran escalated after Iran shot down a US drone and the US sent warships and bombers to the Persian Gulf. The two countries came close to war on several occasions.
2020: Assassination of Qasem Soleimani
In January 2020, the US assassinated Iranian General Qasem Soleimani in a drone strike. Soleimani was the commander of the Quds Force, an elite unit of the Iranian Revolutionary Guard Corps (IRGC). His assassination further increased tensions between the US and Iran.
2021: Return to nuclear negotiations
In 2021, the US and Iran returned to nuclear negotiations under the Biden administration. The negotiations are ongoing, and it remains to be seen whether they will be successful.