U.S. government response to the September 11 attacks

After the September 11 attacks, the United States government responded by commencing immediate rescue operations at the World Trade Center site, grounding civilian aircraft, and beginning a long-term response that included official investigations, legislative changes, military action, and restoration projects. Immediately following the attacks, massive search and rescue operations were launched, and terrorism investigations led to the declaration of war on terrorism that launched military engagements in Afghanistan and Iraq.

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