On the morning of September 11, 2001, 19 hijackers affiliated with the international terrorist network al Qaeda carried out a string of attacks that took the lives of nearly 3,000 people. In the 11 years that passed since the tragic events of 9/11, al Qaeda underwent some dramatic transformations.
The U.S. war in Afghanistan has reduced the group's power base in Afghanistan, while affiliates in west Africa and Yemen have gained in strength. Al Qaeda forged alliances with the Somali militant group al Shabab, carrying out deadly attacks in London and Madrid.
Yet many of al Qaeda's leaders have been captured or killed. According to CNN's Peter Bergen, CIA drone strikes have killed 15 of the most important players in al Qaeda under president Obama, while 16 key al Qaeda operatives in Pakistan were killed during the George W. Bush presidency. The terrorist network lost its longtime leader Osama bin Laden in a U.S. raid on May 1, 2011, as well as its deputy Yahya al Libi in June 2012.
HuffPost World takes a look at al Qaeda's leadership, 11 years after 9/11. Who's still in power? Find out in the slideshow below: