April 22, 2004: NFL football star Pat Tillman is killed in Afghanistan.

Tillman had been serving in Afghanistan as an Army Ranger, a position he achieved after leaving the NFL to join the U.S. military. Tillman's decision to leave a successful football career in order to follow his sense of moral obligation and duty is a quality that has earned him plenty of gratitude and respect, particularly after his death.

Tillman was a standout football player at Arizona State, winning the Pac-10 Defensive Player of the Year award in 1997. He was drafted into the NFL by the Arizona Cardinals.

Despite a successful career, Tillman was deeply affected by the attacks on 9/11 and ultimately chose to forego a football career to serve his country. It was during that service that he was killed by gunfire.

Initially, his death was believed to be caused by enemy combatants. The government later told his family, however, that he may have been killed by friendly fire.

His brother eventually testified before Congress that the government intentionally hid information to try and cover up the failures that led to Pat Tillman's death.

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