The September 11 , 2001 attacks , orchestrated by al-Qaeda , has been called " the worst attack on American soil since the Japanese attack on Pearl Harbor which thrust the United States into World War II " . They involved the hijacking of four large passenger jet airliners because their long transcontinental flight plans meant they carried more fuel , allowing a bigger explosion on impact ( unlike earlier airline hijackings , the primary focus was the planes , not the passengers ) . Two planes were deliberately flown into the Twin Towers of the World Trade Center in New York City , destroying both 110 story skyscrapers within less than two hours , and a third was flown into the Pentagon in Arlington County , Virginia , causing severe damage to the west side of the building . These attacks resulted in the deaths of 221 people ( including the 15 hijackers ) on board the three planes as well as 2,731 more in and around the targeted buildings . A fourth plane crashed into a field near Shanksville , Pennsylvania , after a revolt by the plane 's passengers , killing all 44 people ( including the four hijackers ) on board . In total , the attacks killed 2,996 people and injured more than 6,000 others . The U.S. stock market closed for four trading days after the attacks ( the first time it had an unscheduled closing since the Great Depression ) . Nine days after the attack , U.S. President George W. Bush called for a " War on Terror " and shortly thereafter launched the War in Afghanistan to find and capture Osama bin Laden , the head of the al-Qaeda organization that mounted the 9/11 attacks
September 11 , 2001 attacks
September 11 attacks
Suicide attack