Homeland Security Act of 2002

States that the primary mission of DHS is to: (1) prevent terrorist attacks within the United States; (2) reduce the vulnerability of the United States to terrorism; and (3) minimize the damage, and assist in the recovery, from terrorist attacks that occur within the United States. Includes as DHS's primary responsibilities: (1) information analysis and infrastructure protection; (2) chemical, biological, radiological, nuclear, and related countermeasures; (3) border and transportation security; (4) emergency preparedness and response; and (5) coordination (including the provision of training and equipment) with other executive agencies, with State and local government personnel, agencies, and authorities, with the private sector, and with other entities.

Creates: (1) a Deputy Secretary of Homeland Security, who shall be the Secretary's first assistant for purposes of details; (2) an Under Secretary for Information Analysis and Infrastructure Protection; (3) an Under Secretary for Chemical, Biological, Radiological, and Nuclear Countermeasures; (4) an Under Secretary for Border and Transportation Security; (5) an Under Secretary for Emergency Preparedness and Response; (6) an Under Secretary for Management; and (7) not more than six Assistant Secretaries. Establishes an Inspector General (to be appointed under the Inspector General Act of 1978), and requires the Commandant of the Coast Guard and the Director of the Secret Service as well, to assist the Secretary in the performance of his functions.

Transfers to the Secretary the functions, personnel, assets, and liabilities of specified entities, including: (1) the National Communications System of the Department of Defense; (2) the select agent registration enforcement programs and activities of the Department of Health and Human Services (HHS); (3) the Plum Island Animal Disease Center of the Department of Agriculture (DOA); (4) certain programs and activities of the Department of Energy, such as those specified for Lawrence Livermore National Laboratory; (5) the United States Customs Service of the Department of the Treasury (DOT); (6) the Immigration and Naturalization Service of the Department of Justice (DOJ); (7) DOA's Animal and Plant Health Inspection Service; (8) the Coast Guard; (9) DOT's Transportation Security Administration; (10) the Federal Protective Service of the General Services Administration; (11) the Federal Emergency Management Agency; (12) the National Domestic Preparedness Office of the Federal Bureau of Investigation; (13) HHS' Office of the Assistant Secretary for Public Health Emergency Preparedness; (14) HHS' Strategic National Stockpile; and (15) the United States Secret Service.

Authorizes the Secretary to establish a human resources management system for DHS.

Establishes in the Department of Defense a National Bio-Weapons Defense Analysis Center.