Intercontinental ballistic missiles based in silos have become relatively vulnerable, at least in theory, to counter‐force attacks. This theoretical vulnerability may not, in fact, be a serious practical concern; it is nonetheless troubling both to policy‐makers and to the public. Furthermore, the present generation of ICBMs is aging (the Minuteman II single warhead missile will exceed its operational life‐span early in the next decade) and significant restructuring of the ballistic missile force may well be necessary if a Strategic Arms Reduction Treaty (START) is signed. This paper compares several proposed schemes for modernizing the ICBM force. Because the rail‐garrison MIRVd mobile system is the least costly alternative to secure a large number of strategic warheads, it receives a comparatively large amount of attention.