Kesselschlacht

Encirclement is a military term for the situation when a force or target is isolated and surrounded by enemy forces.

This situation is highly dangerous for the encircled force: at the strategic level, because it cannot receive supplies or reinforcements, and on the tactical level, because the units in the force can be subject to an attack from several sides. Lastly, since the force cannot retreat, unless it is relieved or can break out, it must either fight to the death or surrender.

Encirclement has been used throughout the centuries by military leaders, including generals such as Alexander the Great, Khalid bin Waleed, Hannibal, Sun Tzu, Yi Sun Shin, Shaka Zulu, Wallenstein, Nader Shah, Napoleon, Moltke, Heinz Guderian, von Rundstedt, von Manstein, Zhukov, and Patton.

Sun Tzu and other military thinkers suggest that an army should be not completely encircled but should be given some room for escape, or the 'encircled' army's men will lift their morale and fight till the death. It is better to have them consider the possibility of a retreat. Once the enemy retreats, they can be pursued and captured or destroyed with far less risk to the pursuing forces than a fight to the death. Examples of this might be the battles of Dunkirk, in 1940, and the Falaise Gap in 1944.

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