While no legal obstacles prevent the U.S. Senate's reconsideration of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), lingering doubts (about the effectiveness of the international treaty) and partisan politics (founded upon outdated ideologies of national sovereignty) may again foreclose the opportunity for the United States to lead a just and thorough regime of international arms control. By closely examining the U.S. Senate's previous rejection (and, by implication, the nation's non-ratification) of the CTBT, we assess the political process that failed to realize the security values now imperative to U.S. national defense. To this appraisal, we join analysis of the contemporary law, policy, and science related to U.S. nuclear arms control policy; and we urge that now is the time for the U.S. Senate to reconsider and give its advice and consent for the ratification of the CTBT.