What was targeted on September 11?

On September 11, 2001, the United States was targeted in a coordinated terrorist attack by the extremist group al-Qaeda. Four commercial airplanes were hijacked; two were flown into the Twin Towers of the World Trade Center in New York City, causing their collapse, while a third struck the Pentagon in Arlington, Virginia. The fourth plane, United Airlines Flight 93, was headed for a target in Washington, D.C., but passengers attempted to retake control, leading it to crash in a field in Pennsylvania. The attacks resulted in significant loss of life and had profound global implications, reshaping U.S. foreign and domestic policies.