2. The September 11 Attacks (2001): On September 11, 2001, a series of coordinated terrorist attacks were carried out in the United States by the Islamic extremist group al-Qaeda. The attacks involved hijacking four commercial airliners and crashing them into buildings in New York City and Washington, D.C. The attacks resulted in the deaths of nearly 3,000 people and caused widespread destruction. The September 11 attacks had a profound impact on global politics and led to the U.S. invasion of Afghanistan in 2001 and the Iraq War in 2003.