The Armed Forces Officer Department of the Army Pamphlet 600-2
Chapter 5
RANK AND PRECEDENCE
The regulations that govern precedence among officers of the same service and among the services in relation to each other have a very real utility not only in determining succession to command and as reminders of the authority to which all persons in the Armed Services are subject but in providing precedent for all official or ceremonial occasions in which officers or organizations of the several services may find themselves cooperating. It is easy to imagine the confusion that would result without such rules, especially if a junior commander of a senior service had to defend the right of his organization to occupy the place of honor ahead of a very senior commander with a detachment from a junior service. These regulations are also the arbiter in disputes arising between officers of equal rank who aspire to command of the same unit.
The legislation which separated the Air Force from the Army again raised the question of precedence in parades and ceremonies. Since the Air Force is the junior service, as to date of recognition, the change indicated the following parade order: (Reference, _Federal Register_,