Fog-of-war

The fog of war (German: Nebel des Krieges) is the uncertainty in situational awareness experienced by participants in military operations. The term seeks to capture the uncertainty regarding one's own capability, adversary capability, and adversary intent during an engagement, operation, or campaign. Military forces try to reduce the fog of war through military intelligence and friendly force tracking systems. The term is also used to define uncertainty mechanics in wargames.

The word "fog" in reference to uncertainty in war was introduced by the Prussian military analyst Carl von Clausewitz in his posthumously published book, Vom Kriege (1832), which appeared in English translation in 1873 under the title On War:

War is the realm of uncertainty; three quarters of the factors on which action in war is based are wrapped in a fog of greater or lesser uncertainty. A sensitive and discriminating judgment is called for; a skilled intelligence to scent out the truth.

It has been pointed out that von Clausewitz does not refer to a literal "fog of war," using multiple similar metaphors such as "twilight" and "moonlight" to describe lack of clarity. It was not until 1896 when the literal "fog of war" was used in text, described as "the state of ignorance in which commanders frequently find themselves as regards the real strength and position, not only of their foes, but also of their friends."

The fog of war is a reality in all military conflict. Precision and certainty are unattainable goals, but modern military doctrine suggests a trade off of precision and certainty for speed and agility. Militaries employ Command and Control (C2) systems and doctrine to partially alleviate the fog of war.

Abstract and military board games sometimes try to capture the effect of the fog of war by hiding the identity of playing pieces, by keeping them face down or turned away from the opposing player (as in Stratego) or covered (as in Squad Leader). Other games, such as the Kriegspiel chess-variant, playing pieces could be hidden from the players by using a duplicate, hidden game board.

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