
September 11 attacks
On 11 September 2001, al-Qaeda operatives hijacked four airliners and crashed three of them into the World Trade Center and the Pentagon, with the fourth brought down by passengers over Pennsylvania, killing 2,977 people. The 9/11 Commission's 2004 report established the plot's planning in detail, while the wars in Afghanistan and Iraq that followed are estimated by the Costs of War Project to have contributed to over 4.5 million deaths in the decades since.





