Expert on US-Iran Nuclear Talks: ‘One of the Riskiest Tightropes in Diplomacy Today’

Iranian flag flying above an Iranian city
April 21, 2021

Stephen D. Mull is the University of Virginia’s vice provost for global affairs. Before he arrived on Grounds in 2018, the career U.S. diplomat served as the lead implementer of the Iran nuclear deal, formally called the “Joint Comprehensive Plan of Action,” from 2015 to 2017.

In 2018, then-President Donald Trump withdrew from the pact, meant to constrain Iran’s development of nuclear weapons technology, and pursued what his administration called a “maximum pressure campaign” of crippling sanctions that it hoped would produce a stricter and more comprehensive deal. Now the administration of President Joe Biden is exploring rejoining the agreement.

UVA Today asked Mull for his take on the talks, the challenges facing American negotiators and how a recent attack on an Iranian nuclear facility is affecting the talks.

Q. Can you give our readers an overview of the talks?

A. European, Russian, Chinese, Iranian and American diplomats are meeting in Vienna this month to explore whether it will be possible to restore the Joint Comprehensive Plan of Action on Iran’s nuclear program that the parties successfully agreed to in July 2015. 

Stephen Mull headshot

Former Ambassador Stephen Mull became UVA’s vice provost for global affairs in 2018. (Photo Dan Addison, University Communications)

Although Iran had been complying with the limits the deal imposed on its nuclear program from the start of the deal, the Trump administration decided to withdraw from it in May 2018. Specifically, the Trump administration wanted Iran to renounce the concessions it had won during the negotiations allowing it to engage in limited (and fully monitored) enrichment of nuclear fuel, agree to major constraints on its ballistic missile program and its regional activities, such as its support for Lebanese Hezbollah and the Houthi rebels in Yemen, and end involvement in the Syrian civil war in support of the Assad regime. The original agreement did not address any of those issues, which was a major reason for domestic opposition to the deal in the U.S.

Q. Did Iran remain in compliance with the agreement even after the U.S. withdrew?

A. Despite the U.S. withdrawal in 2018, Iran remained in compliance with the deal for a full year while it pressed the remaining partners to work around U.S. sanctions to accelerate the economic benefits Iran had expected (but not received) from the agreement’s promised sanctions relief. 

After failing in that goal, Iran decided to ramp up pressure on the other parties of the deal, probably to increase its negotiating leverage and to increase pressure on the U.S. to re-enter the deal by systematically and increasingly violating the deal’s restrictions on its nuclear program. It substantially increased its stockpile of enriched nuclear fuel from the 300 kilograms that the agreement allowed for to more than 4,500 kilograms today; enhanced the enrichment levels of its nuclear fuel to far beyond the deal’s limits, bringing it closer to the levels necessary for nuclear weapons; and accelerated the development and use of more advanced centrifuges to permit even higher levels of enrichment.

US and Iranian leaders sitting at an oval table with notebooks talking as they talk about the Iran Nuclear Deal

In this 2016 Oslo photo, Mull, then the lead U.S. coordinator of the Iran nuclear deal, is seated to the left of then-U.S. Secretary of State John Kerry. Iranian Foreign Minister Javad Zarif is fifth from the left. (U.S. State Department photo)

Additionally, the Iranian government threatened to dramatically curtail inspections of its nuclear facilities by the International Atomic Energy Agency, though it has now suspended that threat until May 21, and has threatened to increase its nuclear fuel enrichment level from the current 20% to 60%. (The original deal limited enrichment levels to 3.67%; nuclear weapons require roughly 90% enrichment levels.)

Q. Does the U.S. government have any stipulations before rejoining the Joint Comprehensive Plan of Action? What is the Iranian government’s stance?

A. The Biden administration has pledged it would return to the deal in exchange for Iran’s return to full compliance first.

For their part, Iranian leaders have stated they would return to full compliance only after the U.S. removes all the sanctions it has imposed in violation of the original deal, arguing that as the U.S. was the first to violate the deal, so should be the first to return to compliance. The talks aim to sort out what degree and sequence of sanctions relief by the U.S. would be enough to induce Iran to begin bringing its nuclear program back into compliance. So far, the Iranian delegation has refused to engage directly with American diplomats at the talks, but has reportedly been constructive with European intermediaries, who shuttle back and forth between the Americans and Iranians in Vienna. 

This week, the leader of the Iranian delegation told the press that while serious disagreements remain, the two sides are getting closer to an acceptable roadmap for both sides to return to the deal.

Q. Can you explain what the overall goals are, both for the United States and Iran?

A. For starters, the United States wants Iran to immediately return to full compliance with the agreement’s restrictions on its nuclear programs, including limits on its nuclear fuel stockpile, enrichment levels and centrifuge technology, while maintaining access for sweeping International Atomic Energy Agency inspections of its nuclear facilities. 

For its part, Iran seeks the revocation of all sanctions the United States imposed on Iran since agreeing to the Joint Comprehensive Plan of Action, and the full implementation of the economic benefits that the U.S. agreed to in the deal, such as permitting Iranian oil exports on the world market, unfreezing frozen Iranian assets in third-country banks and allowing the U.S. and European sale of aircraft and spare parts to the Iranian civil aviation industry.

“The talks aim to sort out what degree and sequence of sanctions relief by the U.S. would be enough to induce Iran to begin bringing its nuclear program back into compliance.”

- Stephen Mull

Biden administration officials have also publicly indicated that in addition to Iran’s return to full compliance with the original deal, they would like to make the original deal “longer and stronger” by extending the original deal’s expiration dates on the restrictions on Iran’s nuclear program. They have also indicated they would like to expand the deal beyond nuclear issues to limit Iran’s activities in the region, and to provide for the release of American and other citizens currently held in Iranian jails on spurious charges. Iranian leaders have repeatedly rejected these ideas, but occasionally indicate a willingness to discuss broader regional security issues once the JCPOA is restored, and an openness to prisoner exchanges with the West.

Q. Can you tell us how a recent attack on an Iranian nuclear facility has affected the talks?

A. The attack on the Natanz nuclear site earlier this month was but the latest in a series of covert attacks on the Iranian nuclear program over the years, including the assassination of Iran’s leading nuclear scientist, Mohsen Fakhrizadeh, in November, four other assassinations of nuclear scientists between 2010 and 2012, and a massive cyber-attack on Iranian nuclear facilities with the malicious Stuxnet computer worm beginning in 2010.

Western and Iranian press generally blame either Israel or American intelligence for these attacks, and it’s no secret that a number of close U.S. partners in the region like Israel, Saudi Arabia and the United Arab Emirates viscerally oppose any diplomatic arrangements that allow Iran to enrich any nuclear fuel at all. Some observers say the attacks motivate the various Iranian terrorist and cyber plots against U.S. and Israeli targets that have been reported over the years, though Iran has been associated with terrorist and cyber-attacks in other contexts as well. These include efforts to retaliate against U.S. sanctions, complicate the U.S. military presence in the Middle East, and punish Iranian opponents of the Islamic Republic who live abroad.

The impact of these attacks on broader nuclear diplomacy is unclear, though it was this most recent attack that prompted Iran to threaten to increase its nuclear enrichment levels to 60%; much as increasing sanctions on Iran over the years have typically prompted it to accelerate its nuclear program even more in a bid to amass negotiating leverage for whenever it’s time for diplomacy. So now there is another threat that diplomats will have to try to negotiate away. 

While the attacks have unquestionably and substantially hindered progress in Iran’s nuclear program, at the same time, they have not destroyed the technical knowledge that underpins it. You can’t bomb ideas.

Q. As a former, highly decorated diplomat and Iran expert, could you share any ideas you have for the negotiations?

A. Few Americans would disagree with the goals of successive U.S. administrations to counter Iranian activity that is hostile to U.S. interests, including first and foremost Iran’s threats to the safety of our troops and citizens, which have resulted in the deaths and serious injury of hundreds over the years. It is definitely satisfying and can even be effective (at least in the short term) to deter and retaliate against Iran with the various means at our disposal – diplomatic, military, economic, or otherwise. 

At the same time, there is also a serious risk of entering a spiral of increasing retaliatory violence that could easily lead to miscalculation and acts of war on each side. Remember the Iranian missile attack on the Ukrainian civilian airliner that killed 176 innocent people just over a year ago, in the confused aftermath of the U.S. killing of Iranian military leader Qasem Soleimani?

For our diplomacy to have lasting success in reducing the threat of war and creating secure environments for ourselves and our allies, we really need to look more holistically and objectively at regional security in the Middle East. That should start from the premise that each state – whether Israel, Saudi Arabia, Iran or others – has legitimate security interests that deserve accommodation and respect on a mutual basis. Establishing a predicate that no state should interfere in the affairs of another can produce concrete agreements to stop the sponsorship of proxy forces in other countries that have been so destabilizing over the years, from Lebanon to Yemen and other places in between.

“It’s one of the riskiest tightropes in international diplomacy today.”

- Stephen Mull

Similarly, establishing the principle that each state is entitled to its own defense without threatening others can lay the ground for comprehensive and verifiable arms control agreements. This is hard work, but we’ve done it before, notably in negotiating the Helsinki Accords in the 1970s, which paved the way for the end of the Cold War 15 years later. The United States, with its unrivalled reach and power, is uniquely positioned to play this role.

Getting the nuclear deal back in force could be an important step in this process. Successfully bringing the Iranian nuclear program under verifiable and strict control, while keeping U.S. commitments for sanctions relief, will make a major contribution to reducing regional instability, and maybe, just maybe, lay the foundation for progress in other areas with Iran. But as President Obama used to say, removing the threat of a nuclear-armed Iran for at least a few years is a good enough end in itself.

Q. In your expert view, what challenges are the U.S. negotiators facing following Trump’s abrupt withdrawal from the nuclear agreement in 2018?

A. I suspect one of the biggest challenges the American team is facing in Vienna this month lies in recovering trust among our other negotiating partners after our abrupt and unilateral abrogation of the deal that we worked so hard to negotiate in the 2010s. That will probably require a “down payment” of a swift and substantial lifting of at least some U.S. sanctions in exchange for a tight and specific timeline for Iran’s return to full compliance. It could also help to make a humanitarian gesture to reduce the impact of years of crippling U.S. sanctions on the Iranian people, who after all are not our enemies – for example, by supporting [International Monetary Fund] funding and international cooperation aimed at helping Iran deal with the COVID-19 crisis.

These negotiations take place in extremely challenging political environments in both countries.

In the U.S., Congressional opposition to the nuclear agreement is broad and bipartisan, and moving too swiftly on sanctions relief for Iran could imperil important parts of President Biden’s broader agenda. 

As for Iran, it will elect its next president in June and hard-liners there eager to destroy the Joint Comprehensive Plan of Action could aim to exploit a perception that Iranian negotiators in Vienna had been too soft and elect a president who could be even more hostile to engagement with the U.S. and less willing to compromise on its nuclear program.

It’s one of the riskiest tightropes in international diplomacy today.

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