The United States Department of Justice National Security Division (NSD) handles national security functions of the department. Created by the 2005 USA PATRIOT Act reauthorization, the division consolidated all of the department's national security and intelligence functions into a single division. The division is headed by the assistant attorney general for national security.
The Homeland Security Act (HSA) of 2002 (Pub. L. 107–296 (text) (PDF), 116 Stat. 2135, enacted November 25, 2002) was introduced in the aftermath of the September 11 attacks and subsequent mailings of anthrax spores. The HSA was cosponsored by 118 members of Congress. The act passed the U.S. Senate by a vote of 90–9, with one Senator not voting. It was signed into law by President George W. Bush in November 2002.
HSA created the United States Department of Homeland Security and the new cabinet-level position of secretary of homeland security. It is the largest federal government reorganization since the Department of Defense was created via the National Security Act of 1947 (as amended in 1949). It also includes many of the organizations under which the powers of the USA PATRIOT Act are exercised.