Executive Summary On May 21, the Center for a New American Security (CNAS) hosted an all-day tabletop exercise (TTX) in Washington, D.C., to game out three scenarios related to the crisis surrounding U.S.-Iran tensions over Iran’s nuclear enrichment program and destabilizing regional policies. The intent was to understand how key players would respond and act in these potential scenarios. The TTX included seven teams: the United States, Iran, Europe (representing primarily France, Germany, and the United Kingdom but also the European Union), China, Russia, Israel, and the Gulf Arab States (one player as Saudi Arabia/UAE and the other player as Oman). Teams featured American and foreign regional and functional experts with a deep experience in their respective areas. Players were asked to play the most realistic version of their government. The game examined three scenarios: A continuation of the (at-the-time) low level of U.S.-Iran tension four months into the future;

A more escalatory situation that plays out over the next two years; and

The election of a new U.S. president in 2020 who desires to return to the Joint Comprehensive Plan of Action (JCPOA). Given the recent escalation in tension in June 2019, this report details the findings of the second and third scenarios the TTX examined, which the authors believe are the most relevant. Key lessons from the escalation scenario include: Neither side wants war, and both will look for off-ramps. It will take a dramatic step by the United States, Iran, Israel, or Saudi Arabia to throw the situation into full-scale conflict. But misreads of the other’s steps and lack of channels for engagement increase miscalculation on all sides. As the situation escalates, the United States and Iran may engage in a tit-for-tat cycle that could ultimately move outside their control, leading to an unintended conflict. Israel and Saudi Arabia are wildcards whose unilateral actions could bring the United States and Iran into a direct conflict neither wants. China, Russia, and Europe may come together as a bloc to try and de-escalate. While their influence is limited, the end result will pull Europe away from the United States on the issue of Iran, and potentially other issues in the region, and toward other great powers. Key lessons from the scenario involving an American return to the JCPOA include: A U.S. return to the JCPOA will be incredibly complicated—much more so than people may realize in the lead up to the 2020 U.S. election. Politics in both Iran and the United States will be a major constraining factor, as a new U.S. administration that is not fully staffed tries to negotiate early with a lame-duck Iranian president likely to be replaced by a harder line successor. While the United States will want the JCPOA to be the starting point for a broader and possibly more restraining deal, Iran will want compensation for the American decision to withdraw from the JCPOA in the first place. The United States will need to engage seriously on Israel and Saudi Arabia’s regional concerns or risk having them undermine any diplomatic process. An effort to return to diplomacy with Iran, even if unsuccessful, will strengthen transatlantic ties. The tense relationship between Russia and the United States since the 2016 election significantly complicates future diplomacy with Iran; effective U.S.-Russian cooperation was essential for the JCPOA but may not be possible in a future scenario. In both scenarios, the authors found that Iran and the United States are ultimately the two most important players in this drama. Nothing can substitute for a direct channel between the two.

The Players’ Objectives Before the exercise, all teams were asked to list their country’s strategic objectives and the key domestic and international constraints they faced from the perspective of their country’s current government. Understanding the scenarios in the context of these objectives and constraints helped generate the insights that became the key lessons presented in this report. The United States: The United States’ top objectives were to prevent Iran from acquiring a nuclear weapon and to degrade Iran’s ability to interfere regionally, either directly or through proxies. The United States wished to achieve these objectives while avoiding any serious military entanglement in the region. The United States also considered how its actions could lead to potential disruptions to the global economy and oil market, which would exacerbate the consequences of its existing trade war with China. Deep partisan domestic political disagreements on Iran also limited U.S. options. Iran: Iran’s number one objective was to ensure regime survival. This entailed avoiding a direct major military confrontation with the United States as well as preventing economic collapse and mass political upheaval. Iran also aimed to preserve its nuclear infrastructure, expand its regional influence, strengthen its proxies, and improve its ties with its neighbors. Iran sought to isolate the United States and avoid isolation itself. U.S. sanctions, and by extension a struggling economy; a lack of conventional military capabilities that could compete with the American military presence in the region; and Iran’s partial international isolation infringed on Iran’s ability to achieve its objectives. Europe: Europe wanted to prevent war in the Middle East. The team, which consisted of the E3 (France, the United Kingdom, and Germany) and the European Union (EU), sought to preserve the existence of the JCPOA and Iran’s commitment to the deal. Europe also sought to contain negative effects on regional stability, protect its relationships with regional partners, and counter Iran’s ballistic missile program. The team’s main self-identified limitation was its divergence with the United States on Iran policy and its inability to pursue an independent sanctions policy because its companies were so closely tied to the American financial system, preventing Europe from offering any meaningful economic incentives to Tehran. Further, Europe was frustrated by different priorities and threat assessments between the E3 and other EU members, which inhibited meaningful, unified European action. Russia: Like Europe, Russia wanted to prevent a major war in the region and convince the United States and Iran to save the JCPOA. Beyond that, Russia’s objectives included helping Iran withstand what it viewed as unfair unilateral U.S. sanctions, persuading Iran to show restraint, and preventing the nuclearization of the Middle East. The Russia team saw the biggest challenges to achieving its objectives as being a desire by Israel and some Gulf States to use force against Iran, the desire of the United States to increase economic pressure on Iran, and the difficult relationship between the United States and Russia. China: China’s top strategic objective was to guarantee its energy security, particularly the energy supply from the Middle East, and its transportation routes. Further, China wanted to maintain regional stability and avoid military escalation, preserve cooperation on counter-terrorism efforts in the region, and implement its Belt and Road initiative unimpeded. Finally, China wanted to uphold the non-proliferation regime in the Middle East and beyond. China was constrained by what it saw as hawkish U.S. policies on the Middle East and China, the existing instability in the region, and a lack of mutual understanding between the United States and China. Israel: Israel wanted to prevent Iranian nuclearization. Israel also wanted to avoid all-out confrontation in the region, end the Iranian military presence in Syria, and end the military buildup of Hezbollah. However, Israel acknowledged that it was isolated because its assessment of the Iranian nuclear threat was more extreme than any other actor. Israel was also constrained by its efforts to counter Iran and Hezbollah in Syria and by its desire to avoid a military confrontation with Russia. Saudi Arabia and the United Arab Emirates: Saudi Arabia and the United Arab Emirates’ priorities were to reduce the regional threat Iran posed to Gulf Cooperation Council (GCC) members. In accordance with this objective, Saudi Arabia and the United Arab Emirates also wanted to maintain their strategic alliance with the United States while better leveraging their relationships with China and Russia to pressure Iran. Further, these GCC members sought to solidify their regional alliances with Egypt, Iraqi elements, and Red Sea states. Saudi Arabia and the United Arab Emirates were constrained by their limited military capabilities as well as their reliance on the United States for its military support amid an increasingly tenuous alliance due to U.S. domestic criticism of recent Saudi and Emirati actions in Yemen and elsewhere in the region. Oman: Oman’s top strategic objectives included maintaining excellent relations with Iran, especially at the leadership level, maintaining its key trade and economic relations, and enhancing relations with the United States. This would allow Oman to act as a privileged channel between the United States and Iran. The GCC rift and tensions among Oman, the United Arab Emirates, and Saudi Arabia; Oman’s weak military capabilities; and its elderly leadership; limited Oman’s ability to successfully serve as this channel.

The Escalation Scenario Scenario Design The escalation scenario tested if both sides were to continue to escalate and the situation came to a boiling point, would it eventually lead to conflict or force both sides to return to the negotiating table. The scenario was set in September 2021 under the assumption that it would take some time for the two sides to reach a potential crisis. However, recent events have demonstrated that the scenario’s timing could have been accelerated, as the TTX scenario appears to be much closer to the situation today than anticipated during game design. In the game scenario Iran had fully left the JCPOA in January 2020, and President Trump had been elected to a second term in office later that year. Congress remained split with a Republican-controlled Senate and a Democratic-controlled House. The Trump administration's maximum pressure campaign continued, including a grand bargain trade deal with China that shifted its crude oil demand away from Iran; secondary sanctions on several refineries and traders in China, India, and Turkey had brought Iran’s economy to the precipice. The game projected that the Iranians relied on smuggling and illicit tactics to sell 200,000–300,000 barrels per day—one tenth of what they were exporting when the JCPOA was in effect. With its weakened economy, Iran reconstituted its nuclear program. It enriched uranium to 5 percent and had a stockpile of 6,000 kg of low enriched uranium (LEU)—enough for multiple nuclear weapons if further enriched to highly enriched uranium—and expanded research and development testing of larger numbers of advanced centrifuges. Additionally, it converted Fordow, an underground uranium enrichment facility that had been largely shutdown as part of the JCPOA, back to its enriching capacity and had accumulated 100 kg of 19.75 percent enriched material. This was not yet enough for a nuclear weapon, but it put Iran about two to three months away from a nuclear weapon if it chose to dash to a bomb, a far riskier scenario than the one-year dash-time it faced under the JCPOA. Iran’s June 2021 presidential elections ushered in a hard-liner candidate who ran on a policy calling for accelerating Iran’s nuclear program and pushing back harder against the United States The new Iranian president also positioned himself as the only leader tough enough to effectively negotiate with Donald Trump. Iran and the remaining parties to the JCPOA (excluding the United States) continued to meet sporadically in this time period, but negotiations went nowhere and the EU imposed new sanctions on Iran to address its missile activity. In mid-August 2021, Israeli Prime Minister Netanyahu publicly announced that Iran had an undeclared, secret nuclear facility, similar to Fordow. Iran had yet to begun enriching, but the facility appeared to be an effort to clandestinely enrich uranium for a nuclear weapons program. Finding the information credible, the IAEA requested access to the facility, but Iran denied the request. As Iran pursued an increasingly more aggressive approach to shift the American calculus and demonstrate the costs of the U.S. maximum pressure campaign, Iran conducted a series of proxy attacks, including killing American troops in Iraq; deniable attacks on shipping in the Strait of Hormuz, leading to a major oil spill; and an attack on the East-West pipeline in Saudi Arabia, leading to a dramatic, sustained rise in global oil prices. These escalatory steps in the scenario were accompanied by indicators from both President Trump and the newly elected conservative Iranian president that they were open to dialogue. How the Teams Behaved The beginning of scenario play immediately saw escalatory actions from several teams. However, it appeared that they were trying to avoid an all-out conflict. Iran directed proxies to kill three Americans in Afghanistan; applied political pressure on its allies in Iraq to vote to eject U.S. forces; and deployed to Yemen Afghan Shia proxy fighters, who had previously served in Syria, in a continued effort to demonstrate its strength and try to convince the United States to relax the sanctions that had brought it economy to the brink of collapse. Israel took covert actions, assassinating Iranian nuclear scientists in Tehran and launching a cyberattack on Iranian oil infrastructure to delay Iran’s nuclear program and apply greater economic pressure on Iran. The United States avoided conducting direct military action against Iranian assets inside Iran, as it did not want to start a large-scale war. Instead, the United States responded to Iranian aggression in the region and its renewed nuclear activity by stepping up interdictions and seizures of ships involved in Iranian oil smuggling and reflagging tankers to protect passage through the Gulf in order to reassure its regional partners and signal to Iran that it should deescalate or face a potential conflict with the United States. Meanwhile, both the U.S. and Iranian teams continued to look for channels for dialogue through Oman, yet struggled to open channels due to each one’s distrust of the other and the different agenda, formats, and objectives that they had for the meeting. Still, they moved toward a possible meeting. The situation at this point appeared manageable. However, the scenario dramatically escalated. Saudi Arabia and the United Arab Emirates, frustrated by what they saw as a weak U.S. response and feeling threatened by Iran’s attacks on their energy infrastructure, launched a strike on Iranian oil facilities. Iran responded by conducting sabotage attacks against Saudi oil facilities and launching broad based cyberattacks on UAE government infrastructure. Iran also directed the Shia-Afghan proxies that it had deployed to Yemen to support a Houthi push across the Saudi-Yemeni border toward the southwest Saudi city of Najran. Iran began to drop mines in the Strait of Hormuz. The United States responded to what it saw as a dramatic Iranian escalation, especially its decision to drop mines in the Strait, with limited but significant military strikes on Iranian ships and mine storage depots. Iran responded to U.S operations by directing its Iraqi Shia proxies to kidnap U.S. citizens in Iraq who were working with a U.S. oil company, but to avoid killing any more Americans. At this point, though both sides had walked away from the Omani channel they continued to consider off ramps. By the end of the scenario, the two sides had essentially entered the early stages of a hot war. Key Dynamics The good news from this exercise is that it would likely take a dramatic step by the United States, Iran, Israel, or Saudi Arabia to throw the situation into full-scale conflict. In this scenario the United States and Iran were both interested in managing escalation with each other. Both teams looked for military options short of war that would signal to the other side that they would not be pushed around and attempt to force the other side to back down while at the same time seeking a channel for dialogue through the Omanis. If left to their own devices, the teams would probably have found a way back to the negotiating table. However, as part the scenario, the control team continued to encourage dynamics that identified and tested what it would take to tip the teams into an all-out war, and thus artificially move them toward conflict. Still, there was plenty of bad news. The American and Iranian teams, in their efforts to find ways to deter their opponents and signal that they would not be pushed around, became stuck in a tit-for-tat pattern of escalation as illustrated in Figure 1. The teams felt stuck. The U.S. team would take a forceful action and then look to negotiate. Before negotiations could cement, the Iranian team would retaliate against the Americans, seeking to regain the upper hand before negotiations. This ping-pong continued for several cycles. Although they were unable to establish a dialogue that de-escalated the situation, all the actions taken by both the United States and Iran were intended to remain in the gray zone and therefore be short of spurring all-out war. Both parties, while still escalating, were also looking for potential off-ramps, given neither wanted a large-scale conflict. However, no potential off-ramp was successfully pursued, in part due to the limited amount of time in the TTX, but also because each saw the other as the party responsible for starting the escalation and consistently misread each other’s signals. For example, the Iranians viewed kidnapping Americans as an act of restraint and a way to potentially restart a negotiation with the United States without killing Americans. The American team acknowledged that if the game had gone longer, they would have looked to negotiate over hostages, but they in no way viewed this as a restrained step toward de-escalation. This scenario demonstrated that even with a willingness of both parties to de-escalate, it is hard to actualize in practice. The scenario also showed the dangers of miscalculation. The Iranian team sought to demonstrate that Iran had multiple responses to the United States and its regional partners, and that Iran’s escalation carried significant costs for its opponents without triggering an all-out war. One of Saudi Arabia’s most strategic cities came under ground attack from Iranian proxies, and U.S. citizens in Iraq were kidnapped. Though they remained within the gray zone—short of the line crossing into full conflict— both of these actions were escalatory and made proportionate responses from the United States and its partners difficult. When Iran decided to drop mines into the Strait of Hormuz in response to Saudi and Emirati attacks on Iranian oil infrastructure, Iran miscalculated and went too far. The United States responded with large-scale conventional attacks on Iranian mine storage facilities and other naval assets. Dropping mines was the last straw that caused both sides to back away from any diplomatic channel. Iran had not intended to bring itself into a direct conventional confrontation with the United States, but by miscalculating, going too far, and misreading redlines, it had done just that. Until then, the United States had done all it could to avoid a direct military confrontation at every step, but eventually felt it had no other options.

Regional actors—Israel, Saudi Arabia, and the United Arab Emirates—played a major role in exacerbating the conflict. The Israelis did not necessarily want a war, but they were convinced that the United States would eventually find a way back to the table and cut a deal with Iran that was not in Israel’s interests. This true despite the strong relationship between Israel and President Trump because they feared Trump would eventually negotiate directly with Iran just as he did with North Korea. They also took covert steps early on, including assassinating Iranian scientists and launching a failed covert action against the secret Iranian nuclear facility. These were steps taken to slow Iran’s nuclear program, but were predictably viewed by the Iranians as being joint American-Israeli and only added to the pace of escalation between the United States and Iran. Saudi Arabia was also frustrated with the Trump administration early in this scenario for its continued lack of consultation and its relative lack of direct military action against Iran, though the Saudis remained unlikely to escalate militarily against Iran on their own without the blessing of the United States. However, in this scenario the Saudis and Emiratis did seriously deliberate on unilaterally striking Iranian oil facilities after attacks on their own infrastructure. After hearing this deliberation within the team, the control team encouraged Saudi Arabia and the United Arab Emirates to move forward unilaterally to test the consequences of such action. It was this attack by the Saudis and Emiratis on Iran’s oil installations that triggered an Iranian decision to drop mines in the Strait of Hormuz. This drove the United States to strike Iranian mine arsenals, bringing the United States directly into the conflict. The Saudi-Emirati attack also spurred Iran to greenlight a Shia-proxy Houthi offensive on Najran, Saudi Arabia. The Saudi team acknowledged, after the scenario, that without the control team’s encouragement it likely would not have attacked Iran without American consent. It also explained that Iran’s escalation into southwest Saudi Arabia would have, in the real world and without an artificial end to the scenario, forced the Saudi leadership to focus its primary energy on securing its own territory. Saudi Arabia’s escalation against Iran, and Iran’s responses, demonstrated that the Saudis should be careful when approaching the decision of when and how to escalate against Iran. And while Saudi Arabia would be hesitant to act on its own, Mohammad Bin Salman has demonstrated that in a scenario where he is feeling frustrated by U.S. caution and under attack from Iran, he is perfectly capable of taking a dramatic step that could inadvertently draw the United States and Iran into a major conflict. This development highlighted that the U.S.-Iran tit-for-tit escalation pattern is so vulnerable to external shock that it can easily quicken the pace of escalation and disrupt any de-escalation efforts. While the Israel, Saudi Arabia, and the United Arab Emirates took matters into their own hands, Europe, China, and Russia were limited in their ability to affect outcomes. Perhaps the most significant insight in this scenario was that these three players acted as a bloc; Europe was much more in sync with two of America’s competitors than with the United States. The bloc focused primarily on de-escalation of a major conflict instead of preserving or restarting the JCPOA. China’s priority is energy security. If a regional conflict were to break out, China fears losing its oil from the region, which would be a huge blow to its economy. Russia was focused on stability in its own near-abroad and thought that extreme fluctuations in oil prices were not good for its oil interests, even when it caused higher prices. Russia was also interested in the effect of regional conflict on the Armenian and other minority communities in the region. Concerns of Iranian escalation forced Europe to focus on paths to incentivize Iran to maintain limits on its ballistic-missile ranges after Iran announced in the first move of the scenario that it would no longer do so. Europe tried to revitalize a previous initiative pursued by French President Emmanuel Macron to bring the United States and Iran together, by attempting to modify and present it as appealing to both the United States and Iran. However, while all three parties tried to take their concerns to the UN Security Council and some offered their services to help broker a de-escalation deal between the United States and Iran, they mostly found themselves frustrated and irrelevant. Overall, this scenario demonstrates that neither Iran nor the United States wants war and that both will look for off-ramps. In fact, it will likely take a dramatic step by the United States, Iran, Israel, or Saudi Arabia to throw the situation into full scale conflict. But misreads of the other’s steps and lack of channels for engagement increase miscalculation on all sides. As the situation escalates, the United States and Iran may get into a tit-for-tat cycle that could ultimately get outside of their control.

The Return to the JCPOA Scenario Scenario Design The return to the JCPOA scenario was designed to examine the challenges associated with an American return to the JCPOA. It was set in March 2021, after a Democrat was elected to the presidency, the House of Representative maintained a Democratic majority, and the Senate remained Republican controlled. Iran had left the agreement in January 2020 and had slowly reconstituted its nuclear program. By February 2020, Iran had installed approximately 2,500 IR-1 centrifuges at Natanz, its primary fuel enrichment plant, for a total of approximately 7,500 centrifuges. Additionally, Iran accumulated approximately 3,000 kg of LEU enriched to 5 percent (more than enough for several of weapons if enriched to 95 percent). Iran was in the process of converting Fordow back to an enrichment facility, but had not begun enriching uranium there. Iran’s dash-time to a nuclear weapon had shrunk to six months—down from 12 months while it was adhering to the JCPOA. The supreme leader continued to speak about the United States with themes of distrust and resistance and stated at a ceremonial event that “we know the ways of America, and sweet words do not change our understanding or fool us into believing the words of a country that has lied endless times before.” Iranian parliamentary elections in February 2020 saw the success of hard-liners who ran against the JCPOA. The Iranian presidential elections were due to take place in late May or early June—meaning Iran was heading into election season again. The new U.S. president sought to bring the United States back into the JCPOA, but with caveats. These included that the United States and Iran should begin negotiations on a new, more expansive agreement that would push out the sunset provisions in the JCPOA and begin to address regional disagreements. The other members of the P5+1 strongly encouraged the new U.S. president to return quickly to the JCPOA and commentary in the Arab press focused on the naivety of the U.S. president to return to the deal without considering alternatives. Netanyahu publicly opposed the United States’ returning to the agreement, and rumors circulated that the Israeli government was discussing contingency, planning including military options to defend Israel against an Iranian attack and to strike Iran itself. After conducting a 60-day review of its Iran policy, the new U.S. president announced that the United States would look to immediately begin negotiations with Iran and the P5+1 on these issues.

How the Teams Behaved In contrast to the escalation scenario, the United States started by consulting intensively with the Europeans to discuss the best way to begin negotiations, including a timeline of sanctions relief and a proposal for how both sides could reenter the JCPOA as a way to show goodwill between the United States and Iran. As a mediator Europe was challenged by the distance between the American and Iranian negating positions; the American opening position was to go back into the JCPOA, but to build upon it with additional restrictions on Iran. Yet, the Iranian opening position was that it would go back into the JCPOA only if the United States also provided compensation for the past three years of American violations. With the potential of a new, larger JCPOA, Israel was eager to make sure its concerns about the old JCPOA and the region would be addressed in these new discussions. But the Israelis also took a very hardline, initially refusing to meet with the new U.S. administration except at the highest levels. In addition to meeting with the new president, Israel looked to mobilize its support in Washington, D.C., and the U.S. Congress to oppose what it saw as a bad deal. The Gulf countries were also eager to have their concerns addressed in this new round of discussions and made efforts to show a unified front with Israel when presenting their issues to the United States, who met with both early. Europe also made sure to meet with Russia, the Gulf, and Israel to increase support for new negotiations and eventually called for a meeting between the P5 and Iran in Brussels, which convened near the end of gameplay. At this meeting, the United States’ opening position called for a step-by-step process that would bring Iran into compliance and open the discussion to regional issues in addition to nuclear ones. Iran’s opening position called for compensation for the U.S. withdrawal from the deal and emphasized its willingness to discuss action-for-action steps. Russia and China emphasized their support for negotiations that addressed both nuclear and regional issues. Key Dynamics In this scenario, it turned out to be much more complicated to reenter the JCPOA than anyone had anticipated, even though all the parties were generally interested in returning. Iran’s presidential election was months away. Foreign Minister Zarif and President Rouhani had much less leverage internally to agree to go back to the deal. Meanwhile, the supreme leader and the hard-liners within the Iranian leadership decided to enact a strategy that would test the new U.S. administration’s eagerness to get back into the JCPOA while Rouhani was still in power. Iran sought the unwinding of sanctions as a precondition only for resuming talks concerning the nuclear issue, not for expanding the talks on any other issues, such as regional concerns and ballistic missiles. When the Iranians saw that the United States was reluctant to allow the unwinding of sanctions, the supreme leader and the hard-liners decided to wait until after the Iranian presidential elections to seek seriously negotiations with the Americans. In other words, while the United States was looking for a deal that was better than the JCPOA, so was Iran. The Iranians were also deeply distrustful, arguing that they had already cut a deal with President Obama only to have the next U.S. president walk away from it. How could they be guaranteed that this would not happen again? They were also concerned that a deal with the United States had much less domestic support in Iran after the failure of the JCPOA. Further, Iran was interested in securing a better economic relief package than it had received under the JCPOA and establishing a mechanism to insulate the Iranian economy and protect the new economic package from future U.S. economic pressure if the United States were to violate this second deal. From the perspective of the Iranian leadership, Iran had developed a resistance economy despite the American sanctions pressure, had advanced its nuclear program, and remained a power in the Middle East; these developments were precious and could not be surrendered without significant concessions. On the American side, the first challenge was time. It takes months to get a new administration up and running, and by the time American officials were ready to start serious discussions with Iran, it was only months before the Iranian presidential elections. Moreover, simply going back into the JCPOA was unappealing for the United States because certain provisions of the agreement started to expire within a few years, which would require re-negotiation. Yet, the U.S. team did not know what kind of Iranian leadership it might be dealing with in new negotiations. Despite these challenges, the U.S. team was willing to offer Iran a “more for more” agreement and suggested greater sanctions relief in exchange for more restrictions on Iran’s nuclear program. The U.S. team was also highly constrained by the Israeli and Saudi reaction. Both parties wanted immediate talks with the United States to try to come to an agreement on a set of parameters for a new agreement and what the regional elements of a new deal might look like. Israel emphasized to the United States that if it moved forward on an agreement that did not address regional issues, Israel would mobilize its support in Washington to block the new agreement. Serious discussions on regional issues would involve different players and demand complex approaches to both the guiding principles and the country-by-country details—in other words, a lengthy negotiation. Given the complexities associated with this effort, the U.S. team preferred not to make progress on the nuclear issue entirely contingent on regional negotiations, but it also became apparent that if the U.S. team simply went back into negotiations on the nuclear issue with Iran without a regional framework, it would repeat the same pattern from the JCPOA negotiations. Ignoring the regional issues would incite strong objection from regional partners, as well as at home, that would degrade bipartisan consensus in Washington on the JCPOA (or any other new nuclear agreement), which is essential to the deal’s longevity. Not all regional issues need to be solved as part of a nuclear deal, but if there is no guiding framework to address them upon which the relevant parties agree, in a minimally sequenced or simultaneous process, it will make any return to the JCPOA much more difficult to achieve. In this scenario, the Gulf could do little to act on its frustrations. All the Gulf could do was try and influence the Americans to accommodate their positions on regional issues into a new JCPOA agreement. Israel and the Gulf tried to use their combined weight to influence the United States, but found it had little effect. In contrast to the escalation scenario, Oman had a very marginal role to play, as the United States and Iran had a direct line of communication. On the other hand, Europe—which was largely irrelevant in the escalation scenario—was central to this one. While it might be hard to return to the JCPOA, even an attempt at doing so will be a boost to transatlantic relations. As opposed to the previous scenario in which Europe, Russia, and China teamed up together as mediators, Europe and the United States engaged deeply at the start on how the United States could return to the JCPOA. Though there was no consensus among the European members on exactly what the process should look like, the Europeans did play a role in negotiating with Iran between November 2020 and January 2021 in starting to set conditions for a new round of U.S.-Iranian diplomacy. Europe then engaged with Iran and worked with Russia and China to convene a P5+1 meeting, which became the setting for U.S.-Iran bilateral side talks to begin discussing a way forward on negotiations. Other than joining the multilateral platform, China found it did not have a major role to play in this scenario. China felt it was not in a position with much influence over Iran or Saudi Arabia and, therefore, was vulnerable to the actions of others. The terrible state of U.S.-Russia relations also impeded serious progress on negotiations. In the past, Russia played a critical role in the JCPOA negotiations. When the United States and Russia could agree on something, the Russians were critical to pressing the Iranians to agree. However, the U.S. team barely engaged with the Russians in this scenario, calculating that because of the bad U.S.-Russia relationship, lack of trust, and a domestic political climate critical of Russia, they would not be able to effectively partner on this issue despite some common interests. Additionally, the Russians felt marginalized by this dynamic and were frustrated because they felt that the situation would not be able to positively develop without their involvement. Overall, this scenario demonstrated that a U.S. return to the JCPOA will be incredibly complicated—much more so than people may realize in the lead up to the 2020 U.S. election. Politics in both Iran and the United States will be a major constraint as a new administration that is not fully staffed tries to negotiate early with a lame duck Iranian president likely to be replaced by a harder line successor. While the United States will want the JCPOA to be the starting point for a broader and possibly more restraining deal, Iran will want compensation for the American decision to withdraw from the deal in the first place. In order to be successful, the United States will need to engage seriously on Israel and Saudi Arabia’s regional concerns or risk having them undermine any diplomatic process. Another challenge is that the tense relationship between Russia and the United States will significantly complicate future diplomacy with Iran; effective U.S.-Russian cooperation was essential for the JCPOA, but may not be possible in a future scenario. The most positive development from a U.S. perspective was that an effort to return to diplomacy with Iran, even if unsuccessful, would strengthen transatlantic ties.