Reprisal

A reprisal is a limited and deliberate violation of the laws of war to punish an enemy for breaking the laws of war. A reprisal is not an atrocity. In the United States military, the lowest ranked commander who can authorize a reprisal is the theater commander (i.e. Europe, Middle East, etc).

A related concept is Letter of marque (license to hunt enemy ships and retake lost ships from the enemy).

See also: War, Laws of war.