text: Defense
  Figure 7-1. Kasserine Pass and Sbiba Gap map
  DISTRUPTION
  7-3. The BCT must disrupt the tempo and synchronization of the enemy’s operation to counter the enemy’s
  initiative,to prevent enemy from concentrating combat power against a part of the defense,and to force the
  enemy to go where the commander wants the enemy to go. The commander achieves disruption by defeating
  or misleading enemy reconnaissance forces, impeding maneuver, disrupting reserves, neutralizing fire
  support, and interrupting command and control. Defensive techniques vary with circumstances, but all
  defensive concepts of operation aimto spoil the attacker’s synchronization. Strong security forces to defeat
  enemy reconnaissance,phony initial positions or dummy positions,and obstacles are some of the measures
  used to increase BCT security in the defense.
  7-4. The commander uses counterattack, counterbattery, and countermortar fires; spoiling attacks;
  electromagnetic attacks (see chapter 4); obstacles; and retention of key or decisive terrain to prevent the
  enemy from concentrating overwhelming strength against portions of the defense. Decisive terrain is key
  terrain whose seizure and retention is mandatory for successful mission accomplishment (ADP 3-90). An
  analysis of friendly force networks will inform the development of critical information and provide a basis
  for establishing key terrain in cyberspace. Key terrain in the defense isthose physical and logical entities in
  friendly force technical networks of such extraordinary importance that any disruption in their operation
  would have debilitating effects upon accomplishment of the mission.