Infantry Drills

3-10: Defensive Tasks

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3-10. There are three basic defensive tasks: area defense, mobile, and retrograde. Each contains elements of the others, and usually contains both static and dynamic aspects. Infantry platoons serve as the primary maneuver element, or terrain-controlling units for the Infantry company. They can defend area of operation, positions; serve as a security force or reserve as part of the Infantry company’s coordinated defense. (Refer to FM 3-90-1 for more information.)

3-11. As part of a defense, the Infantry platoon can defend, delay, withdraw,
counterattack, and perform security tasks. The Infantry platoon usually defends, as part of the Infantry company’s defense in the main battle area. It conducts the defense to achieve one or more of the following:

  • Gain time.
  • Retain essential terrain.
  • Support other operations.
  • Preoccupy the enemy in one area while friendly forces attack in another.
  • Wear down enemy forces at a rapid rate while reinforcing friendly operations.

Next: 3-12: Area Defense

Go Back To: U.S. Army FM 3-21.8: The Infantry Rifle Platoon and Squad