SLBM systems have traditionally been seen as counter-value weapons systems, ideally suited to the support of mutual assured destruction and hence of greater international stability. It is the primary contention of this paper that several quite discrete developments are pro viding SLBM systems with a potential, at least under some circumstances, for significant counterforce strategic operations. These developments are partly technical (a combination of improved ballistic missile inertial guidance systems, MIRVing, and increases in the naviga tional accuracy of the FBM submarines), partly strategic, and partly bureaucratic-political. These developments necessitate a re-thinking of much of the conventional wisdom on the role of SLBM systems in the American strategic nuclear posture, and of the implications of these systems for arms control.