Introduction Nuclear nonproliferation is an important priority for US national security. The nonproliferation issue rated very highly in all three National Security Strategies published over the past decade. It is curious, then, that the current US policy approach to the two most high-profile nonproliferation cases boils down to negotiations and “smart sanctions.” As the data in Chapter 3 of this volume demonstrates, Iran and North Korea have been the target of multiple rounds of unilateral and multilateral economic statecraft for the past two decades. There are many explanations for this policy outcome, but one contributing factor is the renewed faith in “smart sanctions” and financial sanctions as a coercive policy tool. Rachel Loeffler recently concluded that, “it is hard to imagine any serious foreign policy issue down the line in which financial tools would not be or should not be considered as part of a comprehensive strategy.” US policy journals have been replete with essays arguing in favor of financial statecraft as the best policy lever available to the United States.