What is the primary mission of the United States Marine Corps?

The primary mission of the United States Marine Corps is to provide combined arms and support for naval and joint operations. This mission emphasizes the Marine Corps' role as a key component of the naval service, working alongside the Navy and other branches of the military. The concept of "combined arms" refers to the integration of different military capabilities—such as infantry, artillery, armor, and aviation—working together to achieve a common objective in operational settings.

In this context, the Marine Corps is specifically organized and trained to conduct rapid amphibious assaults, secure beachheads, and conduct engagements on land following naval operations. This capability allows the Marine Corps to respond swiftly to crises, support the fleet during maritime operations, and project power where needed. The focus on combined arms emphasizes effectiveness and adaptability, particularly in dynamic combat environments.

Other choices reflect important aspects of military operations but do not encompass the core mission of the Marine Corps. Ground warfare and defense operations, while essential, are part of the broader combined arms approach. Conducting humanitarian missions and supporting civilian law enforcement also represent vital activities but do not define the primary operational role of the Corps, which remains centered on naval expeditionary warfare and joint operations.