Collateral Damage

Collateral damage is a general term for deaths, injuries, or other damage inflicted on an unintended target. In American military terminology, it is used for the incidental killing or wounding of non-combatants or damage to non-combatant property during an attack on a legitimate military target. In US military terminology, the unintentional destruction of allied or neutral targets is called friendly fire.

Critics of the term see it as a euphemism that dehumanizes non-combatants killed or injured during combat, used to reduce the perception of culpability of military leadership in failing to prevent non-combatant casualties.

The word "collateral" comes from medieval Latin collateralis, from col-, "together with" + lateralis (from latus, later-, "side" ) and is otherwise mainly used as a synonym for "parallel" or "additional" in certain expressions ("collateral veins" run parallel to each other and "collateral security" means additional security to the main obligation in a contract). The first known usage of the term "collateral damage" in this context occurred in a May 1961 article written by T. C. Schelling entitled "DISPERSAL, DETERRENCE, AND DAMAGE".

The USAF Intelligence Targeting Guide defines the term as the "unintentional damage or incidental damage affecting facilities, equipment, or personnel, occurring as a result of military actions directed against targeted enemy forces or facilities. Such damage can occur to friendly, neutral, and even enemy forces". Another United States Department of Defense document uses "[u]nintentional or incidental injury or damage to persons or objects that would not be lawful military targets in the circumstances ruling at the time. Such damage is not unlawful so long as it is not excessive in light of the overall military advantage anticipated from the attack."

Intent is the key element in understanding the military definition as it relates to target selection and prosecution. Collateral damage is damage aside from that which was intended. Since the dawn of precision guided munitions, military "targeteers" and operations personnel are often alleged to have gone to great lengths to minimize collateral damage.

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