What provides the fundamental principles that guide the employment of U.S. military forces in coordinated action toward a common objective?

Doctrine serves as the foundation for how U.S. military forces operate and is essential for ensuring that all components of the military understand their roles and responsibilities in achieving a unified mission. It encompasses the established principles, practices, and norms that inform command structure, tactics, operational planning, and joint operations.

By defining how forces should be employed and coordinated, doctrine enables effective collaboration among different branches of the military and allied forces. It ensures all military members are operating under the same conceptual framework, which is critical for successful joint operations toward common objectives. Therefore, doctrine is the guiding framework that ensures that actions taken by various military entities are not only aligned but also strategically effective in achieving overarching goals.