Tit-for-Tat Strategies in Trench Warfare Although we focus primarily on business games, game theory is commonly applied in other areas as well, including military situations. One striking example of the titfortat strategy arose in trench warfare in World 1il'v'ar I, as Axelrod {2006} described. No war is pleasant, but the violence in World War I was particularly awful, especially along the EDDmile Western Front in France and Belgium, where Germany and its allies fought against the United Kingdom, France, and their allies. Soldiers on the two sides spent most of their time engaged in trench warfare: hiding in trenches, then occasionally standing up and taking shots at the enemy while hoping not to be shot. However, soldiers were sometimes ordered to charge soldiers in the opposing trenches. These actions usually resulted in a terrible loss of life while moving the front only a short distance. Newcomers to the front were often surprised to discover that soldiers would apparently shoot over the heads of enemy soldiers, deliberately failing to take shots that had a high probability of killing the enemy. A British staff officer on a tour of the trenches remarked that he was \"astonished to observe German soldiers walking about within rifle range behind their own line. Our men appeared to take no notice." The newcomers quickly discovered that a tit-for-tat strategy was being played, often referred to as a \"live and let live" strategy. Axelrod pointed out that the soldiers on the Western Front were engaged in a repeated prisoners' dilemma game. Soldiers needed to shoot their weapons, because the generals and other staff officers behind the lines expected to hear shooting when they approached the front. Given that soldiers had to shoot, they had two possible actions: shoot to kill or shoot to miss. If the game was played only oncea one-day battlethen shooting to kill was a dominant strategy. Regardless of what the enemy did, preventing enemy soldiers from shooting at you by killing or disabling them offered you a better chance of survival than wasting shots. However, the game was played repeatedly, day after day, month after month, often in the same location. In this repeated game, a strategy that led to cooperationnot shooting to killwas feasible. Initially, ifone side happened to unleash an unusually intense and damaging barrage of fire, the other side was likely to respond with an intense barrage of its own. Soon it became apparent that the way to avoid an intense barrage was not to initiate one. Adopting a \"shoot to miss\" strategy could induce the other side to do the same thing. Hence, when an enthusiastic new recruit started shooting aggressively at the enemy, experienced soldiers would yell at him to stop before he got everyone killed, as the enemy would fire back