Which command relationship grants the most authority to a combatant commander?

The command relationship that grants the most authority to a combatant commander is COCOM, or Combatant Command. This authority allows a combatant commander to exercise full command and control over assigned forces, providing them the power to organize and prioritize resources as needed to accomplish missions.

With COCOM, a commander can make decisions regarding planning and execution of operations, manage assigned forces, and allocate resources without restrictions that come with other command relationships. This level of authority is vital for ensuring effective and unified command across various branches of the military, especially during joint operations. It allows the combatant commander to integrate forces and capabilities from different components seamlessly.

The other command relationships, such as TACON (Tactical Control) or OPCON (Operational Control), provide varying degrees of authority but are more limited compared to COCOM in terms of operational scope and resource management. "Support" also implies a more subordinate role, focusing primarily on the assistance provided rather than full command authority. Therefore, COCOM stands out as the paramount command authority that enables comprehensive operational control and strategic decision-making.