The Army includes land combat and service forces and such aviation and water transport as may be organic therein. It will be organized, trained, and equipped primarily for prompt and sustained combat incident to operations on land. It is responsible for the preparation and sustainment of land forces necessary for the effective prosecution of war except as otherwise assigned and, according to integrated joint mobilization plans, for the expansion of the peacetime components of the Army to meet the needs of war. The Army is a total force, comprised of both active and reserve forces.