The Department of Homeland Security (DHS) is a large, multi-faceted agency in the United States Government that combined multiple functions that had been handled most notably by components of the Justice and Treasury Departments. It was created in late 2002 as a direct response to the attacks on September 11th. Its primary responsibility is protecting the United States of America, as well as all U.S. territories. Its budget is currently at approximately $100 billion. DHS employs more than 200,000 people, making it the third-largest cabinet department.
The Department of Homeland Security is headed by the Secretary Janet Napolitano, a former governor of Arizona. She has held that office since January 21, 2009.