Why did George W. Bush declare a War on Terror?

In response to the terrorist attacks on the United States on September 11, 2001, Bush proclaimed himself a war president, leading the nation in a War on Terror. By making this official pronouncement, Bush gained leverage when asking Congress to authorize funds for military operations and made possible the enactment of emergency measures associated with the USA PATRIOT Act. Viewed by Congress and the president as a series of emergency interim regulations during a time of crisis or war, the PATRIOT Act expanded powers for search and surveillance by the Federal Bureau of Investigation (FBI).

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