9/11 Attacks

The September 11, 2001 terrorist attacks — in which 19 al-Qaeda hijackers crashed four commercial planes into the World Trade Center, the Pentagon, and a Pennsylvania field — killed 2,977 people and transformed global politics. The attacks were the deadliest foreign attack on American soil since Pearl Harbor. The US response — the War on Terror, invasions of Afghanistan (2001) and Iraq (2003), the PATRIOT Act, and creation of the Department of Homeland Security — reshaped American foreign policy, global surveillance, and civil liberties. The wars in Afghanistan and Iraq cost over $6 trillion and killed hundreds of thousands, reshaping the Middle East for decades.