The Iranian Nuclear Program (1974–2015)

This chapter analyzes US efforts to prevent Iran from acquiring nuclear weapons from the 1970s until the conclusion of the Joint Comprehensive Plan of Action in 2015. Iran initially began exploring nuclear weapons when it was an American client in the 1970s, prior to the development of a US sanctions policy. Once the United States strengthened its nonproliferation policy, a credible threat of sanctions helped convince Iran to scale back its nuclear plans. After the Iranian Revolution led to a complete break in relations with the United States, Iran again began seeking nuclear weapons, undeterred by the threat of sanctions due to its low dependence on the United States. After two decades of unilateral US pressure failed to alter Iran’s plans, stringent multilateral sanctions led Iran to agree to strict limits on its nuclear program.

The Pakistani Nuclear Program (1972–1987)

This chapter examines US nonproliferation efforts vis-à-vis Pakistan in the 1970s and 1980s. Although Pakistan started its nuclear weapons program prior to the development of a US sanctions policy, and thus underestimated the odds of facing sanctions, it nevertheless went on to acquire nuclear weapons. The United States was unable to halt the Pakistani program for two reasons. First, when it initially threatened and imposed sanctions on Pakistan in the late 1970s, Pakistan was not highly dependent on the United States and therefore had little to lose. Second, once Pakistan became dependent on the United States in the 1980s due to the Soviet invasion of Afghanistan and increased need for aid, the United States undermined the credibility of its nonproliferation policy by waiving sanctions and only credibly threatening to cut off aid in response to a nuclear test.