Nuclear winter creates a dilemma for policymakers. Awareness of that dilemma may not be new, however. Long before the phrase -nuclear winter" became popular, policymakers may well have been aware of the possibility that the indirect effects of a nuclear exchange could be more damaging than the direct effects. Nevertheless, the more widespread public awareness of such a possibility deepens the dilemma and makes it more apparent. The policymakers' dilemma arises from their requirement to create a perception of security from any and all threats. To do this they must be able to credibly threaten to use nuclear weapons in order to deter their use by others. These threats can be tacit, arising from the very existence of nuclear delivery systems, or direct, as evidenced by the instances of missile rattling that have occurred over the years. In either case, such threats begin to ring hallow if the policymakers are known to believe that carrying them out could result in nuclear winter. If policymakers keep secret their personal beliefs about nuclear winter they can still credibly threaten to use nuclear weapons but they have difficulty believing their own threats. Further, they cannot capitalize on the deterrent value of nuclear winter and must live in fear that their bluff may some day be called or that any of the other nuclear powers could cause a nuclear winter out of ignorance.