The US combat mission in Afghanistan officially concluded last week, putting an end to the longest war in American history.
The 13-year war, known as Operation Enduring Freedom, saw the deaths of 2,356 American soldiers, along with thousands of Taliban and Al Qaeda fighters — as well as Afghan civilians.
Roughly 13,000 troops, including 10,000 Americans, will remain in Afghanistan for two years to train and advise Afghan security forces.
On Sept. 11, 2001, al-Qaeda operatives hijacked four planes and crashed them into the World Trade Center, the Pentagon, and a field in Pennsylvania. Nearly 3,000 people died.

None of the hijackers were Afghan nationals. However, President George W. Bush declared a "war on terror" that targeted al-Qaeda and Osama bin Laden, which received shelter and assistance from the Taliban regime in Afghanistan.

Source: White House Archives
Operation Enduring Freedom launched on Oct. 7, 2001 with a bombing campaign against Taliban forces.

Source: Air Force Historical Support Division
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