How did the US repond to the terrorist attacks of September 11 2011?

The U.S. responded to the September 11, 2001, terrorist attacks by launching the War on Terror, which included the military invasion of Afghanistan to dismantle al-Qaeda and remove the Taliban from power. Domestically, the government implemented significant security measures, including the establishment of the Department of Homeland Security and the passing of the USA PATRIOT Act, which expanded surveillance and law enforcement powers. Additionally, the attacks led to heightened security protocols at airports and key infrastructure across the nation.