 Many of the early advances in game theory were made during World War II and the early stages of the Cold War by individuals working with organizations interested in advancing our understanding of nuclear conflict. John von Neumann, for instance, whose early contributions to game theory we described in section 1, did work for the Manhattan Project that was instrumental in the development of nuclear weapons, and he is often credited with having developed the strategy of mutually assured destruction (MAD) that played a prominent role in Cold War nuclear policy (Macrae 1992). MAD is a policy governing the use of nuclear weapons whereby nuclear powers avoid nuclear conflict by credibly threatening to retaliate against a nuclear first strike with a nuclear strike that would be destructive enough to negate any strategic or tactical advantage of a first strike.