What is the primary purpose of the Department of Homeland Security?

The primary purpose of the Department of Homeland Security is to protect the nation from threats, which encompasses a wide range of responsibilities aimed at safeguarding the country from terrorism, natural disasters, and other emergencies. Established in response to the September 11 attacks in 2001, this department leads the efforts in securing the United States' borders, improving transportation security, and enhancing disaster preparedness and response.

The focus on protection is evident in various initiatives and programs, such as counter-terrorism measures, cybersecurity defenses, and emergency management preparedness. These efforts are vital for ensuring the safety and security of citizens and maintaining stability in the face of various potential threats.

Other options presented are not aligned with the core mission of the Department of Homeland Security, as it does not manage foreign trade, oversee the Federal Reserve, or regulate media content. Instead, these tasks fall under different government agencies and departments that specialize in those respective areas.