Border and Immigration Security
DHS manages U.S. borders and immigration enforcement. U.S. Customs and Border Protection (CBP) controls who enters and exits the country. U.S. Immigration and Customs Enforcement (ICE) investigates immigration crimes and detains people entering illegally. Together, these agencies process millions of travelers and check cargo at ports of entry.
Emergency Response and Disaster Relief
The Federal Emergency Management Agency (FEMA), part of DHS, responds to natural disasters like hurricanes, floods, and earthquakes. FEMA provides emergency services, temporary housing, and recovery assistance to communities hit by major disasters. It coordinates with state and local governments to protect people and rebuild affected areas.
Transportation and Airport Security
The Transportation Security Administration (TSA) screens passengers and baggage at airports nationwide. TSA officers use X-ray machines, metal detectors, and other tools to keep airports safe. The Coast Guard, also part of DHS, protects American waterways, ports, and maritime borders.
Counterterrorism and Intelligence
DHS works to prevent terrorist attacks on U.S. soil by collecting intelligence, sharing information with other agencies, and investigating threats. The Secret Service, another DHS agency, protects the President, Vice President, and their families. DHS also works on cybersecurity to defend government and critical infrastructure from online attacks.
Law Enforcement and Criminal Investigation
DHS agencies investigate federal crimes related to immigration, border security, and national security. The Secret Service also investigates counterfeiting and fraud crimes. These investigations help prevent crimes that threaten national security and public safety. 
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