The significant global event that took place on September 11, 2001, was the terrorist attacks orchestrated by Al-Qaeda. The attacks targeted the World Trade Center in New York City and the Pentagon, resulting in tragic loss of life and widespread destruction. This event had profound political implications, leading to the U.S. initiating the War on Terror, which included the wars in Afghanistan and Iraq. It also prompted significant changes in domestic and international security policies, reshaping global relations and perceptions of terrorism. The 9/11 attacks remain a defining moment in contemporary history.