It is equally imperative
that an enemy be deprived of the advantage which their use might
otherwise afford. In both cases localized (even though temporary)
control, not only of the surface but of the water beneath and the air
above, may be essential. It is pertinent, also, to note at this point
the interest of neutrals, or of unneutral nonbelligerent Powers, in
keeping open the trade routes via the high seas. Such interest may
constitute an important factor in the calculations of a belligerent
State.

Considerations of maximum capacity for speed represent the utmost
possibilities with respect to movements (i.e., change of positions)
(page 60) in a given medium within a given time limit. A knowledge of
maximum speed potentialities, one's own and those of the enemy, is
required if changes in position are intelligently to be made. A
knowledge of the variety of conditions, controllable and otherwise,
which affect or preclude the employment of maximum speed, is likewise
a requisite. Poor material condition, inadequate training, and
incorrect methods of operation are preventable or correctable. The
limitations on speed which are imposed by logistics, and by natural
obstacles such as the hydrography, the climate, the wind, the weather,
and the state of the sea, are susceptible of greatest possible
adjustment to circumstances only by the exercise of foresight and
judgment. All these conditions indicate the close relationship that
exists between relative position and freedom of action (page 70).

The same observations apply to considerations of maximum capacity for
endurance, the ability to operate without necessity for replenishment
from an outside source. Radius of action is decreased or increased
accordingly with resultant restrictions, or otherwise, on freedom of
action.

With respect to the freedom of action of armed forces, also a
consideration in relation to feasibility, the logistics of a military
operation, of whatever scope, constitutes a problem which begins when
the plan is in process of formulation. This problem ends only when the
necessity for sustaining the movement, and for retaining the position
gained, no longer exists.

Ships and other means of conveyance, surface, subsurface, and air, are
incapable of providing the necessities of life and the implements of
warfare beyond the capacity built into them. Operations which extend
beyond the limits of such capacity must cease unless replenishment and
support,