How to Ensure Iran Never Resumes Reprocessing

After more than a decade of tensions over Tehran’s nuclear program, the 2015 Iran nuclear deal—formally known as the Joint Comprehensive Plan of Action (JCPOA) —provided the international community a verifiable means to ensure that Iran’s nuclear program would be peaceful in nature. The deal was the result of a hard-fought, two-year negotiation that involved Iran, the European Union, and the P5+1 (the five permanent members of the UN Security Council, plus Germany). Though the negotiation leading to the JCPOA took place over a significant stretch of time—indeed, it was built on the foundation of talks that began in 2003—it’s important to remember that the deal contains critical concessions regarding Iran’s production of plutonium, which the United States had been seeking from Tehran since the 1970s, when the two countries were allies.

Shah Mohammad Reza Pahlavi, prior to his overthrow in 1979, sought to enrich uranium, ostensibly for civilian nuclear power. But he also insisted on Iran’s right to reprocess spent nuclear fuel, which ultimately produces weapons-usable plutonium. The United States staunchly objected—and it is often overlooked that reprocessing was for years a major sticking point between the United States and the Iranian monarch. The disagreement wasn’t formally resolved until the JCPOA effectively blocked Iran’s pathway to a plutonium-based nuclear weapon.

The agreement’s firm provisions against reprocessing, however, extend only until 2031. Critics of the deal often use this sunset provision to argue that the JCPOA delays but does not eliminate Iran’s ability to develop nuclear weapons. These critics ignore the reality that, if the Iranians were to return to reprocessing after 2031, they would have to start from scratch. They would have to contend with intrusive monitoring arrangements that will persist after 2031. And they would have to decide—unlike other nations that have foregone reprocessing—that the technology makes economic, technical, and environmental sense after all. On paper, the JCPOA’s reprocessing provisions don’t last forever. In practice, they very well might.