From political leaders to human rights activists to former Russian spies, assassinations have changed the world.

Beloved politicians like Mahatma Gandhi, John F. Kennedy, and Martin Luther King Jr. were all assassinated.

Most recently, President Donald Trump ordered a US drone strike that killed I ranian Gen. Qassem Soleimani.

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Assassinations have undeniably changed the world.

From Julius Caesar to Mahatma Gandhi, world leaders, activists, and Russian spies have been assassinated for a variety of reasons. But they often didn't have the expected effect.

"Assassinations" have been illegal under US federal law since 1981, though the definition is vague.

Most recently, President Donald Trump ordered the assassination of Iranian Gen. Qassem Soleimani using a drone strike. The administration is officially calling it a "targeted killing."

Iain King, a fellow at the Center for Strategic and International Studies, wrote for NBC that while "the grim record" of assassinations shows that some achieve what they were meant to, a "desired result" is less likely when a government figure is assassinated.

"Even when they are conducted selectively, legally and strategically, history suggests they can still turn out to be unwise," King wrote.

Here are 24 assassinations that have had a major impact.