Ten years after the end of the Cold War, Americans became aware of a realignment in the geopolitical world. Islamic extremist group al-Qaeda hijacked four aircraft and carried out suicide attacks against the Pentagon in Arlington, Virginia and the World Trade Center in New York City.

Almost 3,000 people were killed, the Twin Towers of the World Trade Center collapsed and the whole horrifying event was screened live on TV. President George W. Bush launched Operation Enduring Freedom in response, aiming to oust al-Qaeda and its allies from Afghanistan and Pakistan. In 2014, the tallest building in the western hemisphere opened next to where the towers in New York once stood.

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