Forward Defense Area (FDA)
Unfortunate indeed is the platoon commander or
assistant company commander who is unable to read
The forward defense area extends rearward from
this "writing." The intelligent leader knows that
the defensive line or FEBA to the rear boundaries of
terrain is a major ally and that it virtually decides the
the frontline companies that are used as the forward
positioning of platoons and squads in the defense. The
defense echelon of the battalion. The composition of
defender retains control of terrain features essential to
the forward defense echelon depends upon the form of
observations, communications, and maneuver of
defense used.
reserves. Denying the enemy the use of terrain that
might jeopardize the mission of the battalion is the
Reserve Area
major role of a defender.
To read the "writing on the ground," you can
Extending from the rear boundary of the forward
organize the analysis of weather and terrain primarily
defense echelon (frontline companies) to the rear
around the following set of military considerations
boundary of the defense of the battalion is the reserve
(KOCOA):
area. The reserve forces and those uncommitted
forces under battalion control occupy positions in the
Key terrain
reserve area and add depth to the defensive position.
Observation and fields of fire
The reserve is the principal means by which the
battalion commander influences the defensive battle
Concealment and cover
and regains the initiative.
Obstacles to movement
FUNDAMENTALS OF DEFENSE
Avenues of approach
These considerations are discussed in the
Effective defensive actions are achieved by a
following paragraphs. While the discussions of these
blend of the principles discussed below. The degree
considerations focus on terrain, weather and terrain
to which each principle applies will vary with the
are inseparable. Terrain that offers good traffic
mission and the situation. This is decided only after
conditions when dry may be impassable when wet. A
consideration of all the principles (fig. 4-2).
hill that provides good observation on a clear day may
not provide any visibility on a rainy day or at night.
PROPER USE OF TERRAIN
Maneuvers that are possible and dispositions that
Key Terrain
are essential are indelibly "written on the ground."
Key terrain features must be considered in
formulating defensive tactics. Their selection is based
PROPER USE OF TERRAIN
on the mission of the command. Tactical use of terrain
often is directed at increasing the ability to apply
SECURITY
combat power. Also considered is channeling the
enemy into the beaten zone of organic weapons
MUTUAL SUPPORT
maintained by the battalion. The selection of key
DEFENSE IN DEPTH
terrain varies with the following:
ALL-AROUND DEFENSE
Level of command
Type of unit
COORDINATED FIRE PLAN
Mission of the unit
USE OF BARRIERS
Seabees are normally a service support unit for the
FLEXIBILITY
Marine Air-Ground Task Force (MAGTF). Service
support units need roads over which to move supplies
MAXIMUM USE OF OFFENSIVE ACTION
and secure areas in which to construct facilities.
Aviation units need high terrain on which to set up
radars and communication facilities and large, flat
Figure 4-2.--Fundamentals of defense.
areas for airfields.
