Advocates of additional sanctions maintain that sanctions forced Iran back to the negotiating table, and that if pressure got them to the table, then more pressure will force them to do accede to more of our demands during the negotiations.
Counter-claim: Skeptics maintain that the reasons for Iran’s return to the bargaining table were more complex than supporters suggest, and that domestic economic mismanagement and Iranian politics played a crucial role.3
Detractors of new sanctions insist that the “if some is good, more is better” logic as dangerously simplistic. Any doctor, for example, would object to the same reasoning if applied to prescription medicine. Medicine administered at a certain dosage can improve the health of a patient, but if that patient turns around and doubles it, they might poison themselves. Imposing new sanctions in the middle of a negotiation, critics claim, will poison the negotiations. As the top intelligence official in the United States told Congress, new sanctions “would undermine the prospects for a successful comprehensive nuclear agreement with Iran.”4
More broadly, a “punishment only” approach is likely to fail. If countries make concessions, as Iran did in the JPOA, responding with additional punishments reduces their incentive to make further concessions for a final agreement.5 In addition, Iran has demonstrated a very high capacity to endure pain. Recent sanctions have imposed large costs on the Iranian economy, but Iran suffered greater economic pain from the sanctions imposed during the Iran–Iraq War and endured more than 200,000 casualties. Sanctions alone will not force Iran to capitulate.
Assessment: Both proponents and opponents are partly right. Sanctions did contribute to Iran returning to the negotiations, though it has to be said that the outcome was not automatic. If the hardline candidate, Saeed Jalili, had won the election, he certainly would not have resumed negotiations or agreed to the JPOA—something he opposed as Iran’s nuclear negotiator and as a presidential candidate. Whether more is better would seem to depend very much on context. Should Iran fail to comply with its obligations under the JPOA or clearly put off indefinitely reaching a final settlement, additional sanctions might be useful, but imposing them in the middle of a negotiation and confidence-building phase does not, on its face, appear to be the right time to do so.