An executive department whose main function is to promote safety is?

The executive department primarily responsible for promoting safety is the Department of Homeland Security (DHS). Established in response to the September 11 attacks, its main functions include protecting the nation from various threats, managing disaster response, and ensuring border security. The DHS encompasses several agencies, such as the Federal Emergency Management Agency (FEMA) and the Transportation Security Administration (TSA), all focused on enhancing public safety and security.