ORLANDO, Fla. — While the strained relations between the U.S. and Iran have escalated in the past 24 hours with the U.S. killing of a high-ranking Iranian general, those tensions have been building for a long time.

Gen. Qassem Soleimani, the commander of the Iranian Revolutionary Guard's elite Quds Force, was killed in an American drone strike Thursday — an act many consider the Trump administration's most conseuqential action to date in the Middle East.

"This is a man who's put American lives at risk for an awfully long time," Secretary of State Mike Pompeo said.

The U.S. says Soleimani was behind the recent New Year’s Eve attack on the U.S. Embassy in Iraq that had an Iranian-backed mob storming the compound.

It was the latest conflict between the U.S. and Iran, which dates back decades.

Tensions flared between the U.S. and Iran 40 years ago, in 1979, when 52 U.S. diplomats and citizens were held hostage by Iranians supporting the Iranian Revolution.

The hostages were eventually released, but strained diplomatic relations between the two countries persisted for decades.

Fast-forward to May 2018, when President Donald Trump withdrew the U.S. from Iran’s nuclear deal with world powers. What the president announced meant harsher sanctions against Iran’s crucial oil industry.

A year later, the White House ordered a U.S. aircraft carrier to rush to the Persian Gulf after an unspecified threat from Iran. Soon after, the U.S. blamed explosions targeting oil tankers — crucial for part of the U.S.’s oil supply — on Iran.

The White House said the airstrikes that killed Soleimani were necessary to stop planned attacks on American diplomats and service members in Iraq and throughout the region.

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