commander be common with that of other commanders of
the same echelon who are to participate in the effort enjoined by
their superior's directives. Directives expressed in the Order Form
(page 112 and Chapter VIII) facilitate clear recognition of this
purpose, which appears in the general plan of action prescribed in the
second paragraph of that form. The commander may consider the
relationship thus:

My assigned task is to be accomplished for the purpose of carrying out
my designated part of my immediate superior's general plan.

It is customary to simplify the foregoing to the statement that the
mission is:

(Task) (statement of the assigned task),

(Purpose) in order to assist in the successful execution of (statement
of the superior's general plan).

The words "assist in", etc., may frequently be understood and
therefore omitted.

The foregoing expression of a mission affords, as later explained
(Chapter VI), a method for clear visualization of the effect desired
by higher authority. (See also page 84.)

All of his assigned tasks which materially influence the commander's
Decision (hereinafter discussed) are properly included in his mission;
other tasks, naturally, may be omitted in this connection. In the case
of a double or multiple task (page 86), all the tasks may be related
to a single purpose, or the included tasks may each, or in certain
combinations, be linked separately to appropriate purposes.

Survey of Factors of Fighting Strength. The feasibility and
acceptability of action for the attainment of an objective are
dependent (see the Fundamental Military Principle--page 41) on the
factors of fighting strength. Fighting strength (page 35) is derived
from the means available and opposed, as influenced by the
characteristics of the theater of operations. A survey of these
factors, in proper detail according to the nature of the problem, is
therefore a necessary phase in the process of its solution. Such a
survey completes the basis for the study of courses of action.

Courses of Action. The estimate process naturally takes account (page
80) of methods for attaining the objective indicated in the assigned
task. The military profession has, from time to time, applied a
variety of terms to designate such methods. Terms so used include,
among others, "plans open to us" (or "to the enemy"), "lines of
action", and "courses of action". The last-noted, having been standard
in our naval service for many y