## Yemen Massacre Seen As An Attack-Defense Game

This New York Times Article, “Yemeni Forces Open Fire, Killing at Least 24 protestors,” focuses on the disaster in Yemen where this massacre occurred between these demonstrators and security forces. As the title shows, 24 people died, but over 200 more people were injured during this, with this disastrous situation further adding to a possible civil war in the near future. This horrific event was supposed to be a day of peaceful protesting, yet rebels in civilian cloths were stealthily set on rooftops and shot at security when the march began, leading to an open fire.

However, the real question is, how does a situation like this occur? How did these rebels finally reach this decision to attack, and how did the security decide to retaliate so harshly? This type of situation can be best explained using game theory and described as an attack, defense game. The players in this game are the rebels and the army division (the security). The two plays that could be made would be to either attack, or keep the peace. In this real life and intense situation, each side has to maintain a randomized set of outcomes, for if there was a pure strategy each side would be at a standstill because they would always know what the opponent would do. The army division does not want to be known to only defend, because with that knowledge, the rebels would continually attack until they won. But if they were known to only attack this would most likely cause a setting of continual fear. As for the rebels, if they were known to always attack, then even peaceful protests such as this one would not be allowed to occur for fear of an attack. Yet if they were always known to defend then they would not have any say in the future of their country because they would be too passive.

The game set up basically shows that in this type of scenario, the player either wins or loses. Since Yemen is already so close to a civil war, it is evident that each side is on a relatively even playing field at this point. Therefore, if this were to be a strict attack-defense game, such as with matching pennies, the outcome would be p=1/2 and q=1/2. This Nash Equilibrium is non-exploitable so that each side can maintain the image that they want, while knowing and being prepared that there is a chance that they will be attacked. Although it is believed that the rebels will always attack at all times, if this were true then they would be completely predictable for having a pure strategy. With this massacre that occurred, it shows that the army division was not completely prepared for such an attack, and were therefore caught off guard, just as this randomized equilibrium predicts.

http://www.nytimes.com/2011/09/19/world/middleeast/yemeni-forces-open-fire-killing-protesters.html?ref=world