In the dark of night, U.S. helicopters approached a high-walled compound in Pakistan on a mission to capture or kill one of the world's most notorious terrorist leaders.

Less than 40 minutes later -- early Monday morning in Pakistan -- Osama bin Laden was dead, along with four others inside the complex, and the U.S. forces departed with the slain al Qaeda leader's body to fulfill a vow that originated shortly after the September 11 terrorist attacks on the United States.