Homeland Security
The terrorist attacks of September 11, 2001 caused a seismic shift in how the United States organizes and executes the mission of securing the homeland. The creation and growth of the Department of Homeland Security is the most visible manifestation of this change. However, the homeland security discipline contemplates shared responsibilities and a unity of effort among all levels of government, the private sector, and the general public. The wide array of stakeholders, alongside an expanding definition of what constitutes homeland security, presents complex challenges for policymakers. With the perspective of the more than fifteen years that have elapsed since 9/11, this chapter examines the evolution of homeland security from a near-exclusive focus on terrorism to a broader “all hazards” approach, the relationship between homeland security and national security, the roles of leading actors, and contemporary issues.