All of the branches work together during operations and joint missions in Unified Combatant Commands, under the authority of the Secretary of Defense with the typical exception of the Coast Guard. Each of the Unified Combatant Commands is headed by a Combatant Commander, a senior commissioned officer who exercises supreme command authority per 10 U.S.C. § 164 over all of the forces, regardless of branch, within his geographical or functional command. By statute, the chain of command flows from the President to the Secretary of Defense to each of the Combatant Commanders. In practice, the Chairman of the Joint Chiefs of Staff often acts as an intermediary between the Secretary of Defense and the Combatant Commanders.
One of the oldest military publications is The Art of War, by the Chinese philosopher Sun Tzu. Written in the 6th century BCE, the 13-chapter book is intended as military instruction, and not as military theory, but has had a huge influence on Asian military doctrine, and from the late 19th century, on European and United States military planning. It has even been used to formulate business tactics, and can even be applied in social and political areas.[where?]
Each service has a uniformed head who is considered the highest-ranking officer within their respective service, with the exception of the chairman and vice chairman of the Joint Chiefs of Staff, and the chief of the National Guard Bureau. They are responsible for ensuring personnel readiness, policy, planning and training and equipping their respective military services for the combatant commanders to utilize. They also serve as senior military advisors to the President, the Secretary of Defense, their respective service secretaries, as well as other councils they may be called to serve on. They are as follows:
As in most militaries, members of the U.S. Armed Forces hold a rank, either that of officer, warrant officer or enlisted, to determine seniority and eligibility for promotion. Those who have served are known as veterans. Rank names may be different between services, but they are matched to each other by their corresponding paygrade. Officers who hold the same rank or paygrade are distinguished by their date of rank to determine seniority, while officers who serve in certain positions of office of importance set by law, outrank all other officers in active duty of the same rank and paygrade, regardless of their date of rank. In 2012, it was reported that only one in four persons in the United States of the proper age meet the moral, academic and physical standards for military service.
In the Navy, the rank of Admiral of the Navy theoretically corresponds to that of General of the Armies, though it was never held by active-duty officers at the same time as persons who held the rank of Fleet Admiral. George Dewey is the only person to have ever held this rank. After the establishment of the rank of Fleet Admiral in 1944, the Department of the Navy specified that the rank of Fleet Admiral was to be junior to the rank of Admiral of the Navy. However, since Dewey died in 1917 before the establishment of the rank of Fleet Admiral, the six-star rank has not been totally confirmed.
Although mostly concerned with the military transport, as a means of delivery using different modes of transport; from military trucks, to container ships operating from permanent military base, it also involves creating field supply dumps at the rear of the combat zone, and even forward supply points in specific unit's Tactical Area of Responsibility.
Military law introduces offences not recognised by civilian courts, such as absence without leave (AWOL), desertion, political acts, malingering, behaving disrespectfully, and disobedience (see, for example, Offences against military law in the United Kingdom). Penalties range from a summary reprimand to imprisonment for several years following a court martial. Certain fundamental rights are also restricted or suspended, including the freedom of association (e.g. union organizing) and freedom of speech (speaking to the media). Military personnel in some countries have a right of conscientious objection if they believe an order is immoral or unlawful, or cannot in good conscience carry it out.
While capability development is about enabling the military to perform its functions and roles in executing the defence policy, how personnel and their equipment are used in engaging the enemy, winning battles, successfully concluding campaigns, and eventually the war – is the responsibility of military operations. Military operations oversees the policy interpretation into military plans, allocation of capability to specific strategic, operational and tactical goals and objectives, change in posture of the armed forces, the interaction of Combat Arms, Combat Support Arms, and Combat Support Services during combat operations, defining of military missions and tasks during the conduct of combat, management of military prisoners and military civil affairs, and the military occupation of enemy territory, seizure of captured equipment, and maintenance of civil order in the territory under its responsibility. Throughout the combat operations process, and during the lulls in combat, combat military intelligence provides reporting on the status of plan completion, and its correlation with desired, expected and achieved satisfaction of policy fulfilment.