​Ground Zero

​The World Trade Center site and surrounding area were called this after the collapse of the Twin Towers. The area was filled with 1.8 million tons of debris.

​Manhattan

​Manhattan, a borough of New York City, is considered one of the world’s foremost commercial, financial, and cultural centers. It is mainly located on Manhattan Island.

​The Pentagon

The headquarter building of the Department of Defense for the United States is located in Arlington, Virginia (near Washington D.C.). ​

​hijack

This means to take control by force.

​Afghanistan

​Country in Asia that is mountainous and arid. Terrorists from Al-Queda were allowed sanctuary in Afghanistan. This terrorist group was responsible for the 9/11 attacks.

​Terrorist

​unlawfully using violence and intimidation, especially against civilians, in the pursuit of political aims

​Homeland Security

​Government agency started about 9/11 that united American agencies to prevent future attacks.