Among the functions it is responsible for overseeing are counterterrorism, border security, immigration and customs enforcement, cybersecurity, and disaster management and prevention. It began operating in 2003, making it the newest Cabinet department in the United States. The department was created from 24 existing federal agencies in response to the attacks of September 11, 2001.
While the Department of Defense handles military operations, the Department of Homeland Security works in the civilian sphere to protect the United States at home and abroad. Its purpose is to prepare for, prevent, and respond to national emergencies, especially terrorism. According to geopolitical expert Peter Andreas, the creation of the DHS constituted the most significant government reorganization in the United States since the Cold War.
With more than 200,000 employees, Homeland Security is the third-largest department in the United States federal government, behind the Department of Defense and the Department of Veterans Affairs. Department policy is coordinated at the White House by the National Security Council, with Frances Townsend as Homeland Security Advisor. Other departments with national security responsibilities include the Department of Health and Human Services, the Department of Justice, and the Department of Energy. Criticisms of the department include alleged waste and inefficient use of its substantial financial resources.and the violation of the privacy and civil liberties of American and foreign citizens.
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