Iran-U.S. conflict: How did we get to this point?

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U.S.-Iran conflict timeline: How did we get to this point?

President Donald Trump on Wednesday announced new economic sanctions against Iran hours after Iranian-launched missiles hit two U.S. bases in Iraq.

While Trump condemned Iran’s action, he did not call for a military response, saying instead, “The United States is ready to embrace peace with all who seek it.

The escalation of military actions between the two countries comes days after a drone strike that killed Maj. Gen. Qassem Soleimani, one of Iran’s top military figures. The killing of Soleimani, according to the U.S., came after intelligence sources said Soleimani was planning to attack Americans or U.S. interests in Iraq.

Iran said Soleimani’s killing was an assassination.

Soleimani’s death and Iran’s attack on the two bases are the latest chapter of a complex history between the two countries, peppered more with conflict than cooperation.

From a CIA-led overthrow of the country’s prime minister in the 1950s to the taking of American hostages to the withdrawal from a nuclear deal, here’s a look at how we got to the point in the relationship between the United States and Iran.

What happened most recently that led to Wednesday’s missile strikes by Iran:

On Dec. 27, a U.S. contractor was killed and two U.S. servicemen were injured in a rocket attack against a military base in Kirkuk, Iraq.

The United States claimed the attack was carried out by an Iranian-backed militia called Kataib Hezbollah, a militia that Soleimani dealt with as a proxy for Iran.

On Dec. 29, Trump ordered a missile strike against Kataib Hezbollah forces in Iraq and Syrian territory. The strike killed at least 25 militia fighters.

On Dec. 31, Kataib Hezbollah breached the gates of the U.S. Embassy in Baghdad. They demanded U.S. forces leave the country.

After receiving intelligence reports that Soleimani, leader of Iran’s Revolutionary Guard Corps’ elite Quds Force, was planning an attack on Americans, Trump on Friday ordered a drone strike at the Baghdad airport, targeting Soleimani and killing him.

Vowing “severe revenge,” Iran launched ballistic missiles Tuesday on two U.S. bases in Iraq. No Americans were injured in the attacks.

On Wednesday morning at the White House, Trump announced more severe economic sanctions against Iran but did not threaten military retaliation.

What is the history of the U.S.-Iranian relationship:

1941: Reza Shah Pahlavi, in power in Iran since 1925 and aligned with Nazi Germany, is forced to abdicate the throne by Allied forces. His 21-year-old son, Mohammad Reza Shah Pahlavi takes over as ruler of Iran.

1951: Mohammad Mosaddeq, the prime minister of Iran, spearheads the passage of a bill in Iran's parliament to nationalize the British oil fields there.

1953: Two years later, Mosaddeq's followers force Mohammad Reza Shah Pahlavi to resign. Days later, the U.S. Central Intelligence Agency along with British intelligence agencies work to oust Mosaddeq. The shah is returned to power and becomes an ally of the United States.

1963: Fearing the power an outspoken critic of his plans to modernize the country, the shah sends him into exile. The critic is cleric Ayatollah Ruhollah Khomeini.

January 1979: Sixteen years later, on Jan. 16, 1979, the shah of Iran is forced out of his country amid unrest led by his religious opponents – mainly Khomeini from exile.

As the shah flees the country, Khomeini returns from exile in France. His supporters overthrow the government of Premier Shahpur Bakhtiar, and on April 1, 1979, Khomeini proclaims Iran is now the Islamic Republic of Iran and he is the supreme leader of the country.

Oct. 22, 1979: After being denied admittance by countries around the world, the shah arrives in the United States for treatment of lymphatic cancer.

Nov. 4, 1979: Protesters seize the U.S. embassy in Tehran, taking the Americans working there hostage. Six of the hostages are smuggled out of the country with the help of Canadians, seven are released and one other is let go within weeks for health reasons. The remaining 52 hostages are held for 444 days.

The hostage-takers tell then-President Jimmy Carter they want the shah returned to Iran to stand trial, but the U.S. refuses.

The hostages are released about 20 minutes after President Ronald Reagan is inaugurated on Jan. 20, 1981.

July 27, 1980: Mohammad Reza Shah Pahlavi dies in Cairo.

Sept. 22, 1980: Iran faces an invasion by Iraq and the start of an eight-year war. There is a ceasefire and peace agreement in August 1980.

January 1984: The United States, under President Reagan, designates Iran a state sponsor of terrorism (SST).

1985: In 1985, the U.S. sends weapons to Iran, allegedly in exchange for the country's help to win the release of U.S. hostages held in Lebanon by Hezbollah militants. Money from that action is funneled to U.S.-backed rebels in Nicaragua, creating what will become known as the Iran-Contra deal.

July 3, 1988: A U.S. warship mistakenly shoots down an Iranian passenger plane. According to the Pentagon, the warship believed it was shooting down a jet fighter. The more than 200 aboard are killed.

June 3, 1989: Khomeini dies and Seyyed Ali Khamenei becomes supreme leader.

January 2002: President George W. Bush angers Iranians by saying the country is part of an "axis of evil," along with Iraq and North Korea.

November 2003: According to the International Atomic Energy Agency Iran has been secretly manufacturing small amounts of uranium and plutonium. The IAEA says Iran has been doing so for the past 20 years.

June 2005: Mahmoud Ahmadinejad, the mayor of Tehran, is elected president of Iran. He is reelected in 2009, amid controversy over the election.

Nov. 29, 2011: Protesters storm Great Britain's embassy in Tehran, prompting the staff's evacuation. Two days later, the European Union imposes sanctions on Iranian individuals and businesses. Joining the EU, the U.S. Senate passes economic sanctions against Iran.

September 2013: New President Hassan Rouhani takes office and something that hasn't happened in 30 years takes place – an Iranian president speaks directly with a U.S. president (Barack Obama).

April 2, 2015: Iran agrees to a tentative deal on its nuclear program. The deal includes reducing its stockpile of low-enriched uranium by 98%. A week later, Rouhani says Iran will only sign the agreement if all economic sanctions against the country placed on it by the U.S. and the EU are lifted.

July 14, 2015: The United States and its five partners -- China, Germany, France, Britain and Russia – solidified the deal which is known as the Joint Comprehensive Plan of Action.

Jan. 17, 2016: Iran releases four American prisoners.

Aug. 3, 2016: U.S. officials confirm that the Obama administration arranged for a delivery of $400 million in cash on the same day Iran released the four American prisoners. The Obama administration explains that the money was Iranian money that had been frozen in a trust fund by the U.S., not a payment for the release of the hostages.

Jan. 27, 2017: Days after his inauguration, Trump bans nationals from Iran and other Muslim majority countries from entering the United States for the following 90 days.

Feb. 3, 2017: The U.S., in response to a test of a ballistic missile, enacts more sanctions on Iran.

May 8, 2018: Trump says the U.S. is pulling out of the JCPOA agreement.

Nov. 5, 2018: The U.S. announces it will reimpose the sanctions lifted under the 2015 Iran nuclear deal.

April 8, 2019: The U.S. designates Iran's Islamic Revolutionary Guard Corps as a foreign terrorist organization.

June 2019: The U.S. launches two cyberattacks on Iran.

June 20, 2019: Iran shoots down a U.S. military drone.

June 24, 2019: Trump announces new sanctions against Iran over the drone downing.

July 1, 2019: Iranian Foreign Minister Mohammad Javad Zarif announces that Iran's stockpiles of enriched low-grade uranium have exceeded the 300-kilogram limit set in the JCPOA deal.