Lower Manhattan from a distance with twin towers in sight.

9/11 — September 11th, 2001

Nobody can forget the what happened on 9/11, 2001. No matter what age you were, you knew something was wrong, really wrong.

What happened

19 terrorists hijacked four passenger planes and flew two of them into the World Trade Center buildings in Lower Manhattan. The two towers would last no more than an hour and 42 minutes before collapsing and releasing immense clouds of dust and debris for miles in every direction.

World Trade Center 7 also collapsed due to significant fire damage.

Who was responsible

The Islamic terrorist group Al-Qaeda coordinated the terrorist attacks, which left 2,996 people dead. Thousands more were injured.

In 1988, Osama bin Laden founded Al-Qaeda. It began as a militant Islamist organization, and grew to become a full fledged network of terrorists. Besides the 9/11 terrorist attacks, they've even claimed responsibility for the 1998 U.S. embassy bombings, and the Bali bombings of 2002.

Response by the United States

The War on Terror

The United States swiftly launched a War on Terror. An invasion of Afghanistan followed, in an effort to wipe out the Taliban. Although the Taliban ignored the demands to extradite Osama bin Laden, the U.S. Navy's SEAL Team Six successfully killed him in May 2011.