Defense

A defensive task is a task conducted to defeat an enemy attack, gain time, economize forces, and develop conditions favorable for offensive or stability tasks. (Refer to ADRP 3-90 for more information.) Normally, the defense alone cannot achieve a decision. However, it can set conditions for a counteroffensive or counterattack that enables Army forces to regain the initiative. Other reasons for conducting defensive tasks include, retain decisive terrain or deny a vital area to the enemy, attrition or fix the enemy as a prelude to the offense, counter surprise action by the enemy, or to increase the enemy’s vulnerability by forcing the enemy commander to concentrate subordinate forces. This chapter covers basics of the defense, common defensive planning considerations, forms of the defense engagement area development, and transitions.

1. PREPARATION

The defense has inherent strengths. The defender arrives in the area of operation before the attacker and uses the available time to prepare. These preparations multiply the defense’s effectiveness. Preparations end only when the defenders retrograde or begin to fight. Until then, preparations are continuous. Preparations in-depth continues, even as the close fight begins.

2. SECURITY

Security helps deceive the enemy as to friendly locations, strengths, and weaknesses. It also inhibits or defeat enemy reconnaissance. Security measures provide early warning and disrupt enemy attacks early and continuously.

3. DISRUPTION

Defenders disrupt attackers’ tempo and synchronization with actions designed to prevent them from massing combat power. Disruptive actions attempt to unhinge the enemy’s preparations and, ultimately, his attacks. Methods include defeating or misdirecting enemy reconnaissance forces, breaking up his formations, isolating his units, and attacking or disrupting his systems.

4. MASS AND CONCENTRATION

Defenders seek to mass the effects of overwhelming combat power where they choose and shift it to support the decisive operation. To obtain an advantage at decisive points, defenders economize and accept risk in some areas; retain and, when necessary, reconstitute a reserve; and maneuver to gain local superiority at the point of decision. Unit leaders accept risk in some areas to mass effects elsewhere. Obstacles, security forces, and fires can assist in reducing risk.

5. FLEXIBILITY

The defense requires flexible plans. Planning focuses on preparation in-depth, use of reserves, and ability to shift the main effort. Leaders add flexibility by designating supplementary positions, designing counterattack plans, and preparing to counterattack.

6. MANEUVER

Maneuver allows the defender to take full advantage of area of operation and to mass and concentrate when desirable. Maneuver, through movement in combination with fire, allows the defender to achieve a position of advantage over the enemy to accomplish the mission. It also encompasses defensive actions such as security and support area operations.

7. OPERATION IN-DEPTH

Simultaneous application of combat power throughout the area of operation improves the chances for success while minimizing friendly casualties. Quick, violent, and simultaneous action throughout the depth of the defender’s area of operation can hurt, confuse, and even paralyze an enemy force just as it is most exposed and vulnerable. Such actions weaken the enemy’s will and do not allow all early enemy successes to build the confidence of the enemy’s Soldiers and leaders. In-depth planning prevents the enemy from gaining momentum in the attack. Synchronization of decisive, shaping, and sustaining operations facilitates mission success.