Which command is responsible for conducting homeland defense and DSCA in the United States?

The command responsible for conducting homeland defense and Defense Support of Civil Authorities (DSCA) in the United States is USNORTHCOM. This command's primary mission is to protect and defend the territory of the United States and to support civil authorities in times of need, especially during emergencies or disasters. USNORTHCOM has the authority and capability to coordinate military efforts in response to domestic incidents and works closely with other federal, state, and local agencies to ensure effective response and recovery operations.

In contrast, the other commands, such as USCENTCOM, USTRANSCOM, and USINDOPACOM, have specific regional or functional roles that do not encompass domestic defense responsibilities. USCENTCOM is focused on operations in the Central Command area, USTRANSCOM handles transportation and logistics across all geographic areas, and USINDOPACOM is responsible for the Indo-Pacific region. Therefore, USNORTHCOM is the correct choice as it is specifically tasked with the defense of the homeland and providing support to civil authorities.