In the aftermath of the attacks, many U.S. citizens held the view that the attacks had "changed the world forever." The Bush administration announced a war on terrorism, with the goal of bringing Osama bin Laden and al-Qaeda to justice and preventing the emergence of other terrorist networks.
The United States government created the Department of Homeland Security (DHS) in response to the attacks. DHS is a cabinet-level department of the federal government of the United States charged with protecting the territory of the United States from terrorist attacks and responding to natural disasters.
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