As war rages on in Ukraine, diplomacy is on the cusp of prevailing in Vienna. Against the odds, negotiators are poised to revive the Iran nuclear agreement and block Iran’s pathways to a nuclear weapon—a crucial U.S. interest. According to officials who are familiar with the draft of the agreement circulated in Europe and Tehran in the latter half of August, Iran will once more give up its stockpile of enriched uranium, apart from 300 kilograms enriched at lower levels. It will also cease all enrichment above 3.67 percent and remove thousands of advanced centrifuges from operation. Iran will also have no pathway to a plutonium-based nuclear weapon. Perhaps most important, its nuclear program will once more be fully open to intrusive International Atomic Energy Agency inspections.

If the agreement is formally adopted, it will mark a significant breakthrough for U.S. national security and stability in the Middle East. Instead of contending with Iran inching closer to a bomb, the United States can now look forward to having the Iranian nuclear program in a box at least for the next two years. The aftermath of Donald Trump’s withdrawal from the original 2015 agreement, when Iran returned to a rapid expansion of its nuclear program and came closer than ever to having the material for a nuclear weapon, clearly shows that the United States is better off with the deal than without it. But as it currently stands, the new iteration of the Joint Comprehensive Plan of Action (JCPOA) will be precarious at best.

Critics will contend that the new deal is shorter and weaker rather than longer and stronger. Some of these arguments have merit. Iran’s breakout capability—the amount of time it will take for Tehran to amass the material for a nuclear bomb—will be six to nine months rather than the original 12 months. Still, from a nonproliferation standpoint, even a half year is vastly superior to Tehran’s current breakout capability of roughly a few days. And whereas the original JCPOA contained restrictions of up to 20 years on Iran’s nuclear program, the revived deal may last only as long as a Democrat is in the White House, since key Republican leaders have already publicly committed to killing the deal if a Republican is elected in 2024.

Yet the main reasons why the new JCPOA is more fragile are not internal to the deal but external. There is now deepened mistrust, both in Tehran and in other capitals around the world, about Washington’s ability to uphold international agreements. The current U.S. and Iranian political leaderships also have few domestic incentives to move beyond their shared enmity. As a result, the new Iran deal may come into existence in a strategic context that reduces rather than bolsters its longevity. Still, both sides can take steps to address these concerns and make the deal more durable. If they do not, even this historic breakthrough could be merely a precursor to an even more dangerous crisis.


One of the crucial differences between the initial nuclear deal and its current revived version is the diplomatic environment in which it is taking place. By the time the JCPOA was concluded in 2015, more than two years of direct, face-to-face negotiations between the United States and Iran had built a modicum of trust between the two adversaries. During the second term of U.S. President Barack Obama, Secretary of State John Kerry spent more time with his Iranian counterpart, Foreign Minister Javad Zarif, than he did with any other foreign leader. The two exchanged phone numbers after their first meeting in September 2013 and texted regularly after that. This connection proved helpful well beyond the nuclear negotiations, as for example when several U.S. sailors accidentally drifted into Iranian waters in January 2016. It took Zarif and Kerry just five phone calls and less than 16 hours to secure the release of the sailors in what would have been a significant crisis, had it occurred before the JCPOA was in place.

The renewed JCPOA, on the other hand, has been negotiated not by the top U.S. and Iranian diplomats but by designated envoys on both sides who have yet to speak to each other; Iran has refused direct negotiations. Instead of building trust, the past 16 months of indirect talks have often depleted it. 

Mismatched expectations are a key reason for this dynamic. Although Iran expanded parts of its nuclear program in retaliation for Trump’s betrayal of the deal, it never exited the agreement, out of hope that the United States would return to it once Trump had left the White House. Tehran’s gamble was not based on wishful thinking. As a presidential candidate, Biden called Trump’s exit from the deal “a self-inflicted disaster.” He joined all but one of the 2020 Democratic presidential hopefuls in pledging to swiftly and unconditionally return to the agreement. Rejoining the deal was even written into the Democratic Party platform in 2020.

Biden’s decision not to return swiftly to the deal stunned Iranian officials.

But once in office, Biden was in no rush. Instead of issuing an executive order to return to the agreement on his first day—as he did with the Paris climate agreement and U.S. engagement with the World Health Organization—he chose to keep Trump’s Iran sanctions in place. Then, Biden spent valuable months consulting with Israel, the United Arab Emirates (UAE), and Saudi Arabia, which are fierce opponents of the agreement. In April 2021, Major General Tal Kalman, the head of the Israeli military’s Iran directorate, praised the Biden administration for “keeping its promises [to Israel].” Biden had set out “to listen, not rush to a new deal,” he told the Jewish News Syndicate. Biden’s delay was partly designed to dispel fears among these allies that a renewed JCPOA would lead to a broader thaw between the United States and Iran. In contrast to Obama, who spent months seeking to improve the tenor of U.S.-Iranian relations, Biden did not bother with any confidence-building measures. Instead, to avoid fueling the anxieties of Washington’s partners, he insisted that Iran take the first step—even though it was the United States that had left the agreement. 

Biden’s decision not to return swiftly to the deal stunned Iranian officials, who concluded that he aimed to prolong Trump’s sanctions to force Iran to accept stricter terms. In January 2021, Nasser Hadian, an adviser to the Iranian government then led by President Hassan Rouhani, told The New Yorker that if Biden did not act, “all of Iran’s major factions will push for Iran to increase all aspects of its nuclear program.” That is exactly what happened. After it became clear that Biden was not returning to the deal, Tehran began rapidly expanding its uranium enrichment program. By May 2021, Iran had installed almost 2,000 advanced centrifuges, surpassing both the number it had at any time before the JCPOA and during the Trump presidency. A month later, after a suspected Israeli attack on the Natanz nuclear site, Iran ramped up enrichment levels to 60 percent for the first time, bringing it dangerously close to producing weapons-grade uranium. 

These moves meant that the atmosphere was already poisoned when negotiations began on April 6, 2021. Moreover, Iran had entered its political season, with less than three months to go until a presidential election. The Iranian refusal of direct talks with the United States also made diplomacy less effective and next to useless for trust building. After taking office in August, Iran’s new president, the conservative Ebrahim Raisi, said he neither viewed a nuclear deal as a priority nor saw much promise in rapprochement with the West. He chose Ali Bagheri Kani, a leading opponent of the JCPOA, as his nuclear negotiator. Raisi’s team took months to review the previous negotiations while continuing to add centrifuges and amass enriched uranium, fueling suspicions in Washington that Iran was simply running out the clock until it became a de facto nuclear power. In October 2021, an increasingly frustrated U.S. Secretary of State Antony Blinken warned Iran that the United States was “prepared to turn to other options” if Tehran didn’t change course, implicitly threatening military action.

In less than a year, hopes for a new Iran deal seemed to have been dashed. In the early months of 2021, Biden had slowed down the process, frustrating the Iranians and fueling their suspicions. By the third quarter of that year, it was Iran that was slow-walking diplomacy. Predictably, Tehran’s procrastination only further depleted trust and goodwill. It is even more noteworthy, then, that the two sides have managed to revive the talks and bring them to a final stage in August 2022—a direct result of the most basic truth of successful diplomacy: showing flexibility. Rather than relying solely on pressure and coercion, both the United States and Iran have made concessions to get concessions. But can this achievement prove durable?


Given the current state of U.S.-Iranian relations, it is remarkable that progress has been made at all. In 2015, Zarif famously said that the JCPOA is the floor, not the ceiling, indicating that the JCPOA could set off a larger warm-up between the two countries. “We must now begin to build on it,” he tweeted. The revived JCPOA, however, appears to be the ceiling, not the floor of U.S.-Iranian relations. As it now stands, prospects for expanding on it are slim, for several reasons.

For one thing, political instability and polarization in the United States have rendered any U.S. promise unreliable at best. This new normal, where U.S. presidents can no longer be expected to honor the agreements signed by their predecessors, further deepened Tehran’s apprehensions about renewing the JCPOA. Notably, the Biden administration rebuffed Iranian requests to include binding mechanisms that could prevent a second unwarranted U.S. exit from the JCPOA, asserting that in a democracy, a president cannot tie the hands of his successors. In the end, the changes made to the JCPOA to meet Iran’s demands—such as extending the grace period for foreign companies to wrap up their trade with Iran in case sanctions are reimposed—fall well short of Tehran’s expectations. Instead of signing up for a nuclear agreement that normalized Iran’s trade and investments with the world, Iranian officials had to determine whether only two years of oil sales would be worth giving up vital elements of their nuclear program—and how such a deal would not leave them bereft of leverage in case the United States abandoned the agreement in 2025.

Iran sees little need to seek rapprochement with an untrustworthy United States.

Adding to the challenge are the current geopolitical circumstances. The Russian invasion of Ukraine has strengthened the Raisi government’s preference to look to the East, not the West. From Tehran’s vantage point, the world has become irreversibly multipolar now, creating an environment in which Iran’s geopolitical prospects as a major regional power are set to improve. According to this thinking, Europe is in dire need of Iranian gas and is consumed by the perceived threat from Moscow; China’s and Russia’s growing conflicts with the United States have increased the need of both for strengthened ties with Tehran; and the bifurcation of the global economy between the West and the East will provide Iran with new ways to escape U.S. sanctions. When even some of Washington’s closest partners—including Saudi Arabia and UAE— are hedging their bets and looking for other ways to ensure their security, Iran sees little need to seek rapprochement with a declining and untrustworthy United States.

Similar hesitations abound in Washington. The Biden administration, which didn’t have much appetite for broader engagement with Iran when Rouhani was president, has even less with Raisi in power. The alleged Iranian plot to assassinate John Bolton, who served as national security adviser under Trump, and the attempted assassination of Salman Rushdie by a New Jersey-born Lebanese American who had expressed sympathy for Iran’s theocracy have certainly not increased the White House’s desire to make amends with religious autocrats in Tehran.

But perhaps more important, Washington’s focus is now on China. In the geopolitical contest that Biden envisions, the United States’ vast alliance system constitutes a critical advantage over Beijing. Keeping friends at Washington’s side is essential, even if it entails engaging with leaders who might otherwise be shunned, as Biden did in his July 2022 visit to Saudi Arabia. Given Riyadh’s anxiety over a broader U.S.-Iranian rapprochement, Washington is unlikely to risk pushing Saudi Arabia closer to Beijing for the sake of a larger opening with Tehran. To many observers in Washington, Iran simply isn’t a sufficiently attractive geopolitical prize to justify such a risk. 

Precisely for these reasons, strategists on both sides have assumed that a new iteration of the JCPOA is not likely to last beyond the Biden presidency. The mutual mistrust and question marks about the deal’s durability make it too fragile to withstand the weight of growing U.S.-Iranian tensions on other fronts and the threat of a future Republican-led U.S. re-exit from the agreement. Consequently, Washington and Tehran will likely spend the next two years preparing for a new crisis in 2025. Tehran will seek to make its economy sanctions-proof. Washington will seek to make its military option credible. Acting on the expectation that the new JCPOA won’t survive, however, may make its collapse a self-fulfilling prophecy. If Iran, the United States, and the EU want the renewed JCPOA to stick, they should act accordingly. There are several measures they can take to maximize the prospects of the deal’s survival. 


For Iran, one of the easiest strengthening steps concerns direct diplomacy. With the JCPOA renewed and sanctions lifted, Tehran’s refusal to engage in direct dialogue with Washington will increasingly appear ungrounded. Moreover, U.S.-Iranian talks should not be limited to U.S. Special Envoy for Iran Rob Malley and his Iranian counterpart, Ali Bagheri-Kani, discussing the nuclear deal. Dialogue between the two countries should instead be normalized to the extent possible by establishing direct contact between Blinken and Iranian Foreign Minister Hossein Amir-Abdollahian, as well as between U.S. National Security Adviser Jake Sullivan and Ali Shamkhani, secretary of the Supreme National Security Council of Iran. Neither country’s interest has been served by decades without dialogue, and addressing the nuclear file in a narrow and minimal way will do little to build broader trust between the two sides.

By reestablishing diplomatic channels, both sides can dramatically lower the cost for future governments and administrations to begin talks. Although this doesn’t guarantee that a future Republican administration won’t withdraw from the JCPOA, direct engagement between the two sides may help persuade a future GOP president to stick with the deal. The problem here lies on the Iranian side, but Tehran may have realized the folly of refusing dialogue with Washington. Indeed, Iranian officials told me in 2019 that they believed that had they engaged with Trump in early 2017, he might not have quit the nuclear agreement in the first place. 

A second way to strengthen the deal would be to make it more ambitious. The past few months of negotiations were complicated because the JCPOA was not broad enough to warrant significant political sacrifices, nor was it narrow enough to render its risks negligible. Accordingly, the Biden administration’s effort to seek a larger deal is, in principle, well founded: the necessary amendments to make the deal durable are hard to justify unless the agreement is enlarged. 

The strongest way to ensure U.S. compliance would be to open direct U.S.-Iranian trade.

For instance, the assurance Iran seeks against a second U.S. exit was not fully addressed in the renewed JCPOA but can and should be dealt with in subsequent talks. The original JCPOA did provide such an assurance—snap-back sanctions—but it applied only to Iran. An enlarged agreement should make the cost of violating the deal more symmetric for all parties. After all, Washington cannot claim to be the guarantor of a rules-based international order and also insist it cannot be expected to uphold agreements beyond one political cycle.

The strongest way to ensure sustained American compliance, however, would be to open direct U.S.-Iranian trade. The JCPOA waived U.S. sanctions only on third countries. It did not permit trade between the United States and Iran. Longer restrictions on Iran’s nuclear program could be negotiated in return for lifting primary U.S. sanctions. This would open the Iranian economy to American businesses and create something the original JCPOA lacked—a powerful constituency in the United States that would resist any repeat of Trump’s folly in the future. Hard-liners in Tehran will likely resist such a move, but Iran’s experience with the JCPOA proved the futility of relying solely on secondary sanctions relief. As long as U.S. companies were absent from the Iranian market, pulling out of the JCPOA had little to no economic impact on the U.S. economy.

A third step concerns Washington’s European allies. European diplomats played a critical role in reforging the nuclear agreement, by serving as mediators between the United States and Iran. European governments can play an equally important role in sustaining the agreement by including Iran in their long-term energy security policy. Tehran now puts little value on EU promises since Europe quickly abandoned its trade with Iran after Trump reimposed sanctions. But European negotiators insist that Russia’s invasion of Ukraine has permanently changed their geopolitical calculus: Iran can help shift Europe permanently away from Russian gas, and no Republican president can force Europe to go back to Russian energy. Whether or not this assessment proves true, forging strategic EU-Iranian energy ties will nevertheless help increase the chances that the renewed JCPOA will last while deepening Europe’s influence with Tehran and its role within the nuclear agreement.


A larger barrier to a durable deal, however, is Washington’s use of arms sales to Middle Eastern allies to retain influence in the region. The United States cannot expect an arms control agreement with Iran to endure if it simultaneously seeks to expand the Abraham Accords into an anti-Iran military alliance and to provide ever more sophisticated weapons systems to Iran’s regional rivals. Cementing regional divisions and intensifying Iranian suspicions about its neighbors will only give Iran new incentives to cheat on the agreement and pursue a nuclear deterrent.

There is another way. Regional powers have in the past few years initiated their own de-escalatory diplomacy, in large part facilitated by the Iraqi government in the so-called Baghdad Dialogue. Tehran and Riyadh have held several rounds of talks that helped bring the war in Yemen to a truce. By getting behind this process and by encouraging regional efforts to resolve regional disputes—as well as efforts to strengthen economic ties between Gulf states and Iran—the United States can help further bind Tehran to the renewed nuclear deal. If such moves are successful, it would also create regional resistance—from key U.S. security partners in the Persian Gulf—to a second American exit. Such a dynamic would mark a stark shift from the situation in 2017–18 when the UAE and Saudi Arabia pushed Trump to abandon the JCPOA. 

Many of these steps will be resisted by Washington, Tehran, or both. But if they are not taken, the new JCPOA is unlikely to endure. Surviving one American exit was nothing short of a miracle. Overcoming a second would likely prove impossible.

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  • TRITA PARSI is Executive Vice President of the Quincy Institute for Responsible Statecraft.
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