Title I - Department of Homeland Security
 Sec. 101. Executive Department; Mission.

(a) Establishment. - "There is established a Department of Homeland Security, as an executive department of the United States within the meaning of title 5, United States Code.

(b) Mission. -
(1) In General. - The primary mission of the Department is to-
(A) prevent terrorist attacks within the United States;
(B) reduce the vulnerability of the United States to terrorism; and
(C) minimize the damage, and assist in the recovery, from terrorist attacks that do occur within the United States."

- From H.R. 5005-8 the Homeland Security Act of 2002

Read the Entire text of the Homeland Security Act of 2002 (PDF)