Except as a weapon of last resort, nuclear weapons have no legitimate or compelling military role to play in any conceivable US national security challenge. Yet some policymakers still cling to modernised nuclear weapons for specific tasks in ensuring American security. Since at least 1991, US security has depended almost exclusively on increasingly capable conventional weapons, as effective as nuclear weapons for attacking the most difficult targets. Deterrence through conventional weapons is decisively more credible than through existing or prospective nuclear alternatives. The mere possession of unprecedented conventional military superiority is not enough; a truly effective strategy hinges on perceived effectiveness. Along with addressing conventional needs, America must reformulate its position on nuclear weapons to severely diminish their relevance and solidify the longstanding international taboo against their use.