Suicide attack
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.
After the U.S.-led invasion of Iraq in 2003, Iraqi and foreign insurgents carried out waves of suicide bombings. More attacks have been carried out in Iraq (1938 as of mid-2015) than in any other country.
Outline of the September 11 attacks
On the morning of September 11, 2001, 19 al-Qaeda terrorists hijacked four commercial passenger jet airliners, intentionally crashing two into the World Trade Center in New York City. The hijackers crashed a third airliner into the Pentagon. The fourth plane crashed in a field near Shanksville, Pennsylvania. Nearly 3,000 victims and the 19 hijackers died in the attacks.
The leader of al Qaeda, Osama bin Laden, eventually claimed responsibility for the attacks.The United States launched the War on Terror, invading Afghanistan.The US enacted the USA PATRIOT Act. Many other countries also strengthened their anti-terrorism legislation and expanded law enforcement powers.Some American stock exchanges stayed closed for the rest of the week following the attack and posted enormous losses on reopening, especially in the airline and insurance industries. The destruction of billions of dollars' worth of office space caused serious damage to the economy of Lower Manhattan.The Pentagon Memorial was built adjacent to the building. The rebuilding process has started on the World Trade Center site. In 2006, a new office tower was completed on the site of 7 World Trade Center. The new One World Trade Center was later built and was completed in 2014. Three more towers were originally expected to be built between 2007 and 2012 on the site, but are now delayed to 2018. Ground was broken for the Flight 93 National Memorial on November 8, 2009, and the first phase of construction is expected to be ready for the 10th anniversary of the attacks on September 11, 2011.