A Fuzzy Set Model of NATO Decision-Making: The Case of Short-Range Nuclear Forces in Europe

This article develops a fuzzy set model of group decision-making and then applies the model to the debate that took place between the NATO states in 1989 over whether to modernize the alliance's short-range nuclear missiles or negotiate a force reduction agreement with the WTO. The NATO partners decided what to do at their May 1989 Brussels summit. From among four discernible courses of action - x 1 = modernize, x 2 = negotiate, x 3 = modernize and negotiate, and x 4 = neither modernize nor negotiate - the alliance agreed to negotiate (x 2) with the WTO. It is the organization's path to this decision that is conceptualized as being fuzzy. The sixteen NATO allies' individual preference orderings of the four alternatives are first determined via a content analysis of reports on their discussions. These preference orderings are then used to define a fuzzy group preference relation describing the extent to which each alternative is preferred to the others by the entire alliance. Derived from the fuzzy group relation is then NATO's optimal preference ordering (which, at Brussels, was (x 2, x 4, x 3, x 1)) as well as the organization's fuzzy level of agreement for that ordering (a very weak .56). Subsequent analysis also reveals that the group's optimal preference ordering was the reverse of the United State's preference ordering at the outset of the summit and identical to the preference ordering of Germany. The implications of this outcome for future NATO decisions are discussed.