The character and magnitude of the objective of the highest echelon involved will have considerable bearing upon the number of echelons required for its attainment. Whatever the number, a commander on a particular echelon occupies the position of an immediate subordinate to a commander on the next higher echelon, and that of an immediate superior with relation to a commander on the next lower echelon. Within these confines, authority is exercised and accomplishment exacted, both to the extent calculated to ensure unity of effort.

There may frequently be found two or more commanders occupying coordinate positions on the same echelon, all with the same immediate superior, and all charged with loyalty to him and to each other in the attainment of a common objective. In no case, however, will a commander be directly answerable to more than one immediate superior for the performance of the same duty. Thus is fulfilled the requirement that the command, although relatively narrower in scope as the scale is descended, be reposed in a single head.

The experience gained and the knowledge acquired during early service on the lower echelons provide a basis for later expansion of viewpoint, a better understanding of the position occupied by the subordinate and of the obligations of higher command, including its dependence on subordinates. As the echelons of command are ascended, the details involved become more and more numerous, because of the increased scope of the problems. On the higher echelons, therefore, staff assistance is provided so that the commander may be left free to consider matters in their major aspects. The staff of a commander is not, however, a part of the chain of command; its members, as such, exercise no independent authority.

A chain of command is not created by the subdivision of the officer corps into grades on a basis of relative rank. Such subdivision is for the purpose of classification from the standpoint of potential competency and capacity for responsibility, and carries no authority to command by virtue of rank alone. Organization, systematized connection for a specific purpose, is first necessary.

The armed forces, during peace, are usually subdivided into permanent major organizations for the purpose of attaining and maintaining readiness for action. From the several grades of the officer corps, a permanent chain of command is instituted by the process of organization, the supreme command being reposed in a commander-in-chief. The basis of the permanent organization is that chosen as best suited to attain and maintain readiness. Its choice requires consideration of many factors, such as the types of weapons and vessels, their intended uses, and their capabilities, severally and in combination. Further specific demands are met by temporary arrangements effected through "task organization". Whether the organization be permanent or temporary, its establishment places in effect a chain of command applicable to that organization throughout its continuance.

Habitual and studied adherence to the chain of command in administrative matters, in consultation, in the exchange of information, and in the issue of directives is essential to mutual understanding, and therefore to unity of effort. The right of a commander, however, because of the responsibility he shoulders, to deal directly with subordinates more than one echelon removed is not relinquished because of the existence of the chain of command. Circumstances may arise which require him to issue orders directly to any person under his command. Fully aware, however, of the value of unity of effort, and recognizing that failure to deal through his immediate subordinate, no matter what the exigency, cannot but tend to weaken the chain of command, he will, as soon as the state of the emergency permits, inform intervening commanders of the action he has been compelled to take.

Mutual Understanding. The chain of command, though providing the necessary linkage, does not of itself ensure that the command organization will be adequate, nor can it ensure that unity of effort will result. To meet the requirement of adequacy, there is needed in the person of each commander not only the ability to arrive at sound military decision, to plan, and to direct the operations of his command, but also an appreciation of the position which he occupies in his relationship to his immediate superior, on the one hand, and to his own immediate subordinates on the other. To meet the requirement of unity of effort, it is also essential that there exist a state of mutual understanding throughout the chain of command.

Loyalty is not merely a moral virtue; it is a great military necessity. To establish and to cultivate a state of mutual understanding from which will flow mutual loyalty born of mutual confidence ([page 9]) are prime obligations of command. Within the limits of responsibility and resultant authority, individual initiative will follow. On a foundation of intelligent cooperation and resolute determination, the acts of the lowest commander will be in accordance with the desires of the highest. This, in effect, will constitute unity of effort, accomplished through the vesting of command in a single head.

The final aim of mutual understanding is attained when, in the absence of specific instructions, each subordinate commander in the chain acts instinctively as his immediate superior, if present, would have him act, and also cooperates intelligently with commanders occupying coordinate positions on the same echelon. For this reason there is need, on all echelons, of a complete grasp of the significance of the relationship between immediate superior and immediate subordinate, and of the obligations of each to the other.

The proper relationship is such that a subordinate, even though separated from his commander, can confidently take action as if the latter were present. To this end, the competent commander will earlier have cultivated the personal relationship between his immediate superior and himself, and between himself and his subordinates. It is through such close relationship that mutual understanding is best developed and harmony promoted, so that intelligent and cordial unity of effort may exist among the personnel of a command.