The Department of Homeland Security (DHS) is a prominent U.S. federal executive department, headquartered in Washington, D.C. Established in response to the September 11, 2001, terrorist attacks, it represents the largest reorganisation of the U.S. federal government since 1947. Its primary mission is to safeguard the American people, homeland, and values from various threats. The DHS focuses on anti-terrorism, border security, immigration and customs, cybersecurity, transportation security, and disaster prevention and management. It plays a crucial role in securing critical infrastructure and enhancing national resilience.