An Acute Power Imbalance Helped Doom the Iran Nuclear Deal

With the U.S. and its partners at odds, U.S. economic and political power allowed it to stand alone against the international community

By  Rosaleen Carroll

One of the best things about teaching is that the instructor often learns from his or her students. That was the case with the author of the following commentary, which is based on a term paper she wrote while taking my class at George Washington University on Iran-U.S. relations. As we mark the sixth anniversary of the unilateral U.S. withdrawal from a landmark nuclear deal with Iran, her commentary helps explain why that deal was so hard to sustain. Barring a dramatic shift in U.S. or Iranian policies, progress with Tehran is likely to be incrementable even as Iran’s rapidly developing nuclear program makes such progress all the more essential.” — Barbara Slavin, Distinguished Fellow, Middle East Perspectives

Wednesday, May 8 marks six years since then President Donald Trump withdrew from the Iran nuclear deal, the Joint Comprehensive Plan of Action (JCPOA). Campaigning for president and at the outset of his administration, Joe Biden promised to revisit and try to revitalize the agreement. By 2022, however, Biden called the deal “dead.” Given Iran’s support for Russia against Ukraine and backing of anti-Israel forces in the latest Middle East conflict, as well as Biden’s desire to achieve re-election, any significant new Iran nuclear agreement seems very far away.

Javad Zarif, the Iranian foreign minister during and for several years after the JCPOA negotiations, had hoped that the agreement would serve as a “solid foundation” rather than a “ceiling” for U.S.-Iran ties. Instead, it further eroded a long-strained relationship.

The chances that the JCPOA could lead to a true bilateral breakthrough were undermined from the start by the massive power imbalance between the two key participants.

Officially adopted in 2015 and implemented in January 2016, the JCPOA negotiations involved the U.S., China, Russia, France, the UK, and Germany – the so-called P5+1 – plus Iran and the European Union. The goal was to drastically limit Iran’s ability to make a nuclear weapon in exchange for sanctions relief and other economic benefits. In 2018, however, despite Iranian compliance, Trump pulled the U.S. out of the deal and imposed a policy of “maximum pressure,” imposing new sanctions on top of existing ones. Iran remained compliant for a year, then resumed ramping up uranium enrichment, while stirring up tensions in the Persian Gulf. After a series of incidents capped by the U.S. assassination of Iranian Gen. Qasem Soleimani in early 2020, the two sides nearly went to war.

The JCPOA’s dissolution should have come as no surprise, given the skepticism about the deal in key constituencies. Leadership in both countries withheld explicit endorsement of the negotiations, and public sentiment in the U.S. was negative. In a survey taken after then President Barack Obama announced the pact’s completion, only 33% approved, while 45% disapproved and 22% had no opinion. Public support in Iran was stronger, but in a 2015 poll, 21% disapproved of the deal and 85% believed it was very important for Iran to continue its nuclear program. Obama only managed to achieve implementation of the agreement through a tortuous path that let the deal go forward through executive orders absent disapproval by two thirds of Congress. The JCPOA thus became a deeply partisan issue in the U.S., with Trump promising withdrawal as a key plank of his first presidential campaign.               

The second foundational flaw in the JCPOA was a deep imbalance in the application of incentives and disincentives. Iran had to agree to gut its nuclear program, while the U.S. had only to suspend part of its Iran sanctions. After suffering a loss of more than $100 billion under U.S. and international sanctions, Iran saw relief from even some of these restrictions as critical to its economic wellbeing. Iran was thus willing to severely limit its uranium enrichment and stockpile, dismantle and reduce its centrifuges, and agree to unprecedented intrusive monitoring by the International Atomic Energy Agency (IAEA). No similarly weighty incentives and disincentives applied to the U.S. The JCPOA provided no real consequences for U.S. withdrawal, while the losses suffered by Iran upon the re-imposition of sanctions were devastating.

The disparity in the JCPOA’s terms was exacerbated by the process by which U.S. sanctions were relieved, the temporary nature of the relief, and the so-called “snapback” policy. The U.S. procedure was defined in the Iran Nuclear Agreement Review Act (INARA), passed by Congress. It required the president to certify Iran’s compliance every 90 days; if the president failed to do this, Congress could fast-track legislation to reimpose sanctions or the president could simply stop waiving sanctions. INARA’s conditions for certification were also broader and less specific than those of the JCPOA–leaving them open to subjective interpretation–and there were no evidentiary requirements for withholding certification. INARA thus enabled a U.S. withdrawal from the JCPOA without cause or consequence to Americans and provided for the swift reinstatement of U.S. sanctions, regardless of Iran’s compliance with JCPOA requirements. 

The JCPOA also contained an unprecedented provision concerning UN sanctions. The so-called “snapback” policy allowed for sanctions to quickly “snap back” under certain circumstances. Any party to the deal could submit a non-compliance complaint against Iran to a dispute resolution panel. If the complaint remained unanswered after 30 days, the UN sanctions would automatically “snap back” without requiring a vote of the Security Council, thus rendering the reversion veto proof. Conversely, preventing this default “snapback” would require a Security Council vote, where any single member could veto the move to halt sanctions. Proponents argued that the country most likely to violate the JCPOA’s terms would be Iran, and that a rapid re-imposition of UN sanctions would be an effective deterrent. In the end, however, it was the U.S. that violated the deal undeterred.

In a purely political gesture, the Trump administration attempted to invoke snapback even after it was no longer a participant in the JCPOA. Most UN and Security Council members protested, asserting that the U.S. lacked legal authority to invoke the snapback. Nevertheless, the Trump administration declared the UN sanctions to be in effect, adding that failure to comply with them would be punished by the U.S.

Because the U.S. is a global superpower, its exit from the JCPOA and re-imposition of sanctions forced other nations — especially European partners — to accept the agreement’s implosion. The U.S. imposes “secondary” sanctions targeting non-U.S. actors that conduct commercial activity with a primary sanctioned country. While the European Union created a vehicle to try to continue trade with Iran, European companies would not risk jeopardizing their U.S. markets. The initiative was cancelled and Europe-Iran trade shriveled.

The most significant thread running through any discussion of the JCPOA’s flaws is the imbalance of power between the two primary players. The JCPOA was a negotiation between a global superpower and a regional actor. In the case that the U.S. and its partners were at odds, U.S. economic and political power allowed it to stand alone against the international community. Whatever the wishes of the other JCPOA participants, the JCPOA could not survive without U.S. support.

Given their disappointing experience with the JCPOA, Iranian officials are understandably wary of accepting a new deal without large incentives and durable guarantees. The two sides did manage a lesser understanding in 2023 that slowed Iran’s accumulation of highly enriched uranium and freed five U.S. dual nationals in return for unfreezing some of Iran’s oil revenues in South Korean banks and transferring the money to Qatar. However, Iran has not been able to access those funds because of the Gaza War even as it has conducted new indirect talks with the U.S. in an effort to keep that war from escalating.

Nuclear experts from Iran, the U.S. and Europe have discussed other ways to contain Iran’s nuclear program and U.S.-Iran tensions. One possibility is that the U.S. could adopt a framework memorializing a slow and steady repeal of more sanctions in return for a larger nuclear rollback. A well-considered program of sanctions relief would help establish U.S. bona fides for both Iran and the international community, but any such move is unlikely during a U.S. election year or in the aftermath of a new Middle East conflict.

International agreements involving nations of such disparate power start on an uneven playing field. But multilateral international agreements like the JCPOA should not be held hostage to a single country’s political headwinds.

Rosaleen Carroll will be a recent graduate from the George Washington University’s Elliott School of International Affairs, where she studied International Affairs and Arabic with a focus on the Middle East. She has written on numerous topics concerning the region, including the conflict in Afghanistan, labor unions in Tunisia and Egypt, the Arab Spring, and Wahhabism, and intends to work in journalism or policy research specializing in Middle Eastern affairs and politics.

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