After multiple failed rounds of nuclear diplomacy in Vienna and Doha, talks between Iran and the P5+1 (the United States, the United Kingdom, France, Germany, Russia, and China) are back on in Vienna. The revived talks first hit a snag earlier this year when Tehran raised several new demands, including the removal of the Islamic Revolutionary Guard Corps (IRGC) from the State Department's Foreign Terrorist Organizations (FTO) list.1 Washington initially balked but reportedly then acquiesced to a partial solution: removing secondary sanctions on companies doing business with the IRGC.2
"I am absolutely sincere... when I say that Iran got much more than it could expect," said Russian diplomat Mikhail Ulyanov back in March.3 The deal now on the table is far better for Tehran than the one to which Ulyanov referred.
Admittedly, the regime has more than once pumped the brakes on nuclear diplomacy. This intransigence signaled that Ayatollah Ali Khamenei, the Islamic Republic's supreme leader, may not have ever wanted an agreement at all. Rather, he may seek to prolong talks to advance the regime's nuclear program while avoiding harsh decisions by the Board of Governors of the International Atomic Energy Agency (IAEA). Still, recent news out of Vienna suggests a deal may be imminent, with even more Western concessions.
This memo chronicles Tehran's dangerous nuclear advances in recent years, the results of American-led diplomacy to curtail this activity, and the actions Israel has taken both to encourage greater American leverage and to hinder Iranian progress.
Iran's Quest for a Nuclear Weapon
For more than three decades, Tehran has worked, with varying degrees of intensity, to develop a full-fledged military nuclear program. Its leaders deny this, citing a purported fatwa, or Islamic ruling, from Khamenei that abjures nuclear weapons.4 Israel ultimately proved Iran's assertion false in 2018, when the Mossad exfiltrated from a Tehran warehouse a secret nuclear archive documenting the clerical regime's efforts to develop a nuclear weapon.5
The archive revealed that Iran's covert nuclear weapons program, which began in the late 1990s, was far more advanced than Western intelligence had previously assessed. One of the documents included handwritten instructions by Iranian leaders to the program's directors, ordering them to design, build, and test five 10-kiloton nuclear warheads. Attached to the document were blueprints for a warhead and descriptions of a plan to affix it to a long-range ballistic missile.6
The regime in Iran is a signatory to the Nuclear Non-Proliferation Treaty (NPT), which theoretically should restrict its nuclear ambitions. However, this has not stopped Tehran from building uranium enrichment facilities and concealing them from the IAEA, the UN body that monitors and verifies Iran's nuclear commitments.7
For a country to become a nuclear-threshold state, it must develop three key components: fissile material (enriched uranium or plutonium); a weapon system to detonate the fissile material; and a delivery system to carry the weapon. Once a nation completes these steps, its acquisition of a nuclear weapon depends not on technology or capability, but only on political will and timing. In such a situation, military intervention or regime change may constitute the only means to prevent a larger crisis.
The Iranian regime has worked for years to master all three components. But progress has not been linear. In 2003, Tehran curtailed but did not end its nuclear weapons development,8 likely fearing an attack by the West in the wake of America's invasion of Iraq. The regime may or may not have resumed those weaponization activities. If it has, it is probably keeping a low profile, mostly under the cover of academic work.
Nevertheless, the Islamic Republic has steadily added to its nuclear gains for 15 years and counting. In 2007, it initiated enrichment at the Natanz nuclear site,9 which had been covert until an Iranian opposition group exposed it in 2002.10 In 2009, the United States, the United Kingdom, and France exposed another underground enrichment site in Fordow, located in the Iranian province of Qom.11 Months later, in 2010, the regime began enriching uranium to 20 percent purity at Natanz,12 likely to gain leverage in future negotiations.
The level of 20 percent purity is significant. While a nuclear weapon requires a few dozen kilograms of uranium enriched to more than 93 percent, the time and effort to enrich natural uranium to 20 percent purity accounts for the majority of the process.
Between 2006 and 2010, the UN Security Council imposed four rounds of nuclear and economic sanctions on the regime.13 Between 2010 and 2013, Washington imposed additional sanctions that crippled the Iranian economy.14 Yet Tehran defiantly continued to expand its nuclear program, ultimately amassing large quantities of uranium enriched to 5 percent as well as a smaller amount enriched to 20 percent.15
Israel, in turn, launched what it described as the "war between wars" — an asymmetric "gray zone" campaign targeting Iranian assets related to Tehran's nuclear and conventional military capabilities. According to various sources, this campaign included cyberattacks against Iran's nuclear facilities.16
Fears mounted in both Washington and Tehran about a possible Israeli military strike.17 This prompted an international effort to reach an agreement that would halt Tehran's program. Yet the more the West endeavored to meet Iran's demands, the more the regime increased them. Tehran advanced its nuclear program and committed additional NPT violations. This was the case a decade ago. It is the case now.
While various initiatives to engage Tehran were reported in the decade prior, the first serious effort to negotiate with the Iranian regime began in 2011. The Obama administration understood the importance of securing Israeli support for the negotiations given the threat that Iran posed to the Jewish state. The administration sought to use confidence-building measures to reassure Israel and other nervous Middle Eastern allies. Thus began a series of U.S. visits to meet with senior Israeli officials. American officials said they sought an interim deal that Iran would reject, thereby making it easier for the UN Security Council to impose additional sanctions, possibly without the objection of Russia and China.
Still, the Obama team argued that even if Iran accepted the interim plan, in full or in part, the final agreement would meet Israeli demands, based on the limitations specified by the Security Council. Jerusalem stated that the only suitable outcome would be "zero, zero, zero." Tehran could have no enrichment facilities or centrifuge research and development (R&D); no plutonium, heavy water reactors, or separation plants; and no fissile material inside Iran.
However, while one American team was building trust with Israel, secret negotiations between the United States and Iran began in Oman in 2012.18 The talks were led by figures now holding key positions in the Biden administration: National Security Advisor Jake Sullivan and CIA Director William Burns, then serving as the State Department's director of policy planning and deputy secretary of state, respectively.19 These secret negotiation laid the foundation for both the 2013 interim agreement, formally known as the Joint Plan of Action (JPOA), and the 2015 final agreement, the Joint Comprehensive Plan of Action (JCPOA).
In exchange for minimal nuclear concessions, the JPOA granted Iran — for the first time — a de facto authorization to enrich uranium,20 contravening multiple Security Council resolutions. This concession directly reneged on the Obama administration's pledge to Israel. The agreement, designed to last six months,21 lasted two years as Iran and world powers repeatedly extended talks past self-imposed deadlines.22 The deal effectively rewarded Tehran with cash every month simply for negotiating. Billions of dollars in sanctions relief injected new life into Iran's sanctions-battered economy.23
With negotiations underway, Israel formed a group of experts from the Israel Defense Forces' Military Intelligence Directorate and Planning Directorate, the Mossad, the National Security Council, the Ministry of Foreign Affairs, the Ministry of Defense's Political-Military Division, the Israeli Atomic Energy Commission, and the Ministry for Strategic Affairs. While Israel was not a party to the negotiations, the group of experts worked intensively with the world powers negotiating with the Iranians. Jerusalem aimed to underscore the dangers of an agreement that failed to permanently prevent Iran from acquiring a nuclear weapon.
The team of experts forwarded dozens of technical papers to the American and other negotiators. They called for an Iranian breakout time — the time needed to produce enough fissile material for one nuclear bomb — of at least several years rather than merely one year (as proposed in the talks). The Israeli experts wanted Tehran to dismantle all enrichment infrastructure and ship it out of Iran. They called for a full disclosure of the Iranian nuclear program's "possible military dimensions" (PMD).
The experts also sought a complete cessation of Iranian R&D on advanced centrifuges, as well as assurances that Iran's Arak reactor would not be a heavy water facility. They recommended the retention of sanctions on the Islamic Republic for at least 20 years, if not longer. These recommendations went largely unheeded.
A Deal Is Struck
The final round of talks lasted approximately nine consecutive weeks in 2015, concluding with the finalized JCPOA on July 14.24 The deal gave Iran nearly everything it wanted, primarily due to the other side's eagerness to reach an agreement. Communication between the Israeli experts and the U.S. negotiators broke down. The Obama administration blamed Prime Minister Benjamin Netanyahu's March 2015 speech to the U.S. Congress — delivered against the wishes of the president — criticizing the emerging deal.25 But this was not the only reason. The discussions were simply no longer productive. The American negotiators wanted an agreement at almost any cost, and Israel's protests were no longer welcome.
Thus, even as Tehran continued to call for the annihilation of Israel,26 the JCPOA provided the regime with a clear path to nuclear weapons and the ability to acquire the necessary infrastructure. The agreement effectively enabled Iran to become an internationally recognized and legitimate nuclear-threshold state.27 The regime also reaped a massive financial windfall, enabling an alarming increase in Iranian support for terrorist groups across the region — Hezbollah in Lebanon, Hamas in Gaza, and the Houthis in Yemen, among others.28 No less alarming for Israel: The JCPOA provided a template for other Middle Eastern countries to pursue the status of a threshold state.
Moreover, UN Security Council Resolution 2231, which endorsed the agreement, codified the JCPOA's sunset provisions. Per the resolution, the UN arms embargo on Iran expired in 2020 even though Tehran had repeatedly violated it by sending weapons to violent proxies and terrorist groups in the Gaza Strip, Lebanon, Syria, Iraq, Yemen, and Bahrain.29 Resolution 2231 also removed the ban on Iranian tests of "ballistic missiles designed to be capable of delivering nuclear weapons." The resolution merely "call[ed] upon" Tehran to halt its missile development, and even that non-binding language will expire next year.30 Since 2015, Iran has tested dozens of ballistic missiles.
The Israeli Response
The Israeli cabinet issued a statement rejecting the deal on the day of the JCPOA's finalization.31 Thereafter, the Israeli government launched a campaign to educate Congress and the broader U.S. public about the loopholes, gaps, and other flaws in the agreement.32 It was a last-ditch effort to prevent the deal from entering into force.
It was no use, however. Congress failed to muster the necessary votes to stop the agreement. By the end of 2015, the IAEA prematurely closed its investigation of the PMD of Iran's nuclear program,33 paving the way for the JCPOA's implementation in January 2016. The Iranian economy soon received billions of dollars in sanctions relief,34 enabling a conventional military buildup and a surge in terror sponsorship worldwide.35
Apart from concealing from the IAEA the existence of a secret nuclear weapons archive, undeclared nuclear sites, and undeclared nuclear material, Iran abided by most of its other commitments under the deal. Tehran understood that patience was all that was needed to ultimately gain a legitimized nuclear program along with massive economic benefits. This calculus was upended when President Donald Trump pulled out of the agreement in 2018.36 Before he made his final decision, however, the administration offered the Iranians opportunities to negotiate a more comprehensive agreement. They refused.37
Tehran treaded carefully at first but then substantially increased its violations following the November 2020 election of President Joe Biden, who signaled an eagerness to return to the deal and removed a credible U.S. military threat from the equation.38
Russia, China, and Europe assert that Iran's nuclear violations were the result of Washington's unilateral withdrawal.39 However, the most egregious Iranian violations did not occur until 2021, after Biden's election and the subsequent renewal of negotiations.40 Tehran appeared to seek leverage for these talks.
In response, Israel has increased the intensity of its war between wars. According to a wide range of Israeli and other sources, this campaign has impeded Iran's military expansion in Syria and limited the regime's efforts to supply its Lebanese terrorist proxy, Hezbollah, with lethal precision-guided munitions.41 More importantly, Israel has reportedly acted against Iran's nuclear program, eliminating senior nuclear officials42 as well as some physical components.43
Returning to the JCPOA
Israel's shadow war notwithstanding, the regime's nuclear advances have rendered a return to the old agreement futile. Iran's nuclear progress since 2015, and particularly since Biden's election, is beyond the point of containment.44 This underscores why the original deal was a mistake. The data disclosed by the nuclear archive,45 as well as new information obtained by IAEA inspectors since 2015,46 show that the JCPOA failed to account for the full range of Iranian nuclear activities, including activities that preceded the agreement.47
Between the JCPOA's finalization and America's 2018 exit from the deal, the Iranian regime increased uranium enrichment and added advanced centrifuges, as permitted under the agreement.48 This enabled Iran to transition to clandestine underground enrichment.49 The regime already had second-generation IR-2M centrifuges operating in the Natanz underground facility, even though the JCPOA prohibited it.50
Worse, the agreement did not bar the regime from stockpiling raw materials or producing advanced centrifuges. This undermined optimistic calculations of Tehran's breakout time projected by supporters of the deal. Iran has already mastered the enrichment technology needed to amass enough fissile material for a weapon.
As Secretary of State Antony Blinken ceded in April 2022, Iran's breakout time was "down to a matter of weeks."51 Since then, the regime's breakout time has reportedly dropped to near zero.52 A return to the original agreement as written is therefore futile.
The Failures of the IAEA
The decision to close the PMD investigation was among the West's biggest mistakes. Today, the regime insists this issue is not open for discussion.53 Regime negotiators now demand that all IAEA investigations — new and old — be closed or written off. This is reportedly one of the remaining sticking points in Vienna.54
Regardless of the terms of any deal that is reached, the regime in Iran is much closer to a bomb than previously estimated. The IAEA has only recently reached this conclusion, thanks largely to Israeli evidence. The nuclear watchdog appears incapable of fulfilling its mandate independently.55 This alone raises troubling questions about the feasibility of a sustainable agreement, which would require reliable monitoring and verification.
A fundamental aim of the 2015 deal was to establish airtight, unprecedented inspections of Iranian nuclear sites. The IAEA's strict inspections were supposed to be the most effective tool in the agreement.56 Yet these inspections, which never extended to military sites or sites connected to Iran's secret nuclear-military Organization of Defensive Innovation and Research, missed the nuclear archive and all the nuclear sites and activities the IAEA subsequently discovered thanks to the archive. In the meantime, the IAEA has repeatedly put JCPOA violations on the back burner for the sake of preserving the agreement.57
The IAEA director general, Rafael Grossi, has repeatedly traveled to Tehran in an attempt to reach new understandings with the regime.58 Yet Tehran has accelerated its nuclear activities, breaching not only the JCPOA but also the NPT, Iran's Comprehensive Safeguards Agreement with the IAEA, and the Additional Protocol. The IAEA's failure to address these violations has severely damaged its credibility and could effectively end the agency's status as an independent body.
The Iranian Strategy
The Iranian nuclear strategy appears to be based on four assumptions. The first is that the United States, under its current leadership, lacks the will to attack Iran's nuclear facilities. This view has yielded a second — and erroneous — belief that Israel lacks sufficient capabilities to strike Iran's nuclear program and will not attack without American support. Third, the Islamic Republic believes its economy can withstand Washington's current economic pressure, which is significantly weaker than the sanctions of past administrations. And finally, the regime believes it faces no meaningful internal threats to its survival. These four views explain why Tehran has not exhibited any flexibility at the negotiating table.
With negotiations now at a pivotal moment, Jerusalem's primary concern is that Washington will agree to a "JCPOA-minus." The White House is reportedly willing to offer sanctions relief that goes far beyond the JCPOA's concessions. In particular, the Biden team has offered to lift sanctions on thousands of individuals and entities, including Iranian banks, the supreme leader, and his inner circle.59 Moreover, U.S. Special Envoy for Iran Rob Malley and his team, together with some EU high officials, have explored ways to comply with the Iranian demand to remove IRGC-related entities from the FTO list despite promises from the White House to the contrary.60
Offering additional concessions to the regime is irresponsible, particularly amidst a spate of regime-inspired attacks and plots on American soil.61 Moreover, Iran is already enriching uranium at 60 percent,62 manufacturing and testing advanced centrifuges, and blocking the IAEA's access to active nuclear sites and other locations where violations have occurred in the past.63 Tehran refuses to dismantle the advanced centrifuges it has produced in violation of the 2015 agreement.64
And the clock is still ticking. In 2027, the JCPOA's limitations on the regime's industrial-scale production and installation of centrifuges, including advanced ones, will expire.65 In 2031, the deal's restrictions on Iranian fissile-material stockpiles and enrichment, including to weapons-grade, will expire, too.66 Enrichment at Fordow and the building of new enrichment plants will be permitted. The bans on processing plutonium, storing heavy water, and constructing heavy water reactors will be lifted. Tehran will be in a position to produce dozens of bombs.67
Toward A Better Agreement
Should the Biden administration wish to negotiate a deal that would truly restrain Iran from attaining a nuclear weapon, it must address the three key steps for becoming a nuclear-threshold state. The IAEA should strictly prohibit Tehran from producing fissile materials and or possessing the technology needed to develop a bomb. This cannot be subject to negotiation. Without such restrictions, the Iranians will be three to five months away from a nuclear weapon — with tacit international approval.
Additionally, while the United States and Israel have long measured Iran's nuclear progress in terms of breakout times, this concept is no longer helpful. Tehran has no intention of "breaking out" to a weapon. Rather, it will "sneak out" in undisclosed underground facilities using advanced centrifuges that enrich at much higher speeds.
Any viable deal must force the regime to come clean about its past activities, reopen the PMD investigations closed in 2015, and answer all questions stemming from new findings. The United States cannot conclude a worthwhile deal if Iran fails to confess to its past violations and fully disclose all its previous nuclear activities.
Finally, addressing the Iranian regime's delivery systems, primarily ballistic missiles capable of carrying nuclear warheads, requires more than weakly worded UN resolutions. The missile-test ban, already rendered toothless in 2015, will expire entirely in 2023. A better agreement should put a permanent stop to the development of these missiles, even if the regime says this is non-negotiable.
Recent Iranian and American Positions
In nuclear talks over the past year, Iranian negotiators introduced several new demands. In addition to its requirement to remove the IRGC from the FTO list, Tehran called for guarantees for compensation in an event of another American withdrawal.68 The regime also sought to close all the IAEA's open files and to end all investigations, past and present.
In effort to demonstrate it has not capitulated to the regime's terms, Washington made new demands: Tehran must commit to halt aggression in the Persian Gulf, particularly by curbing the IRGC's activities there, and to communicate directly with Washington. The viability of such an arrangement is questionable given the regime's past behavior and stated goal of destabilizing the region. Interestingly, U.S. efforts to reach a "longer and stronger" accord, as the Biden team promised upon his election, have ended.69
An immediate concern is that the JCPOA's restrictions will soon sunset. In 2025, world powers will lose the "snapback" mechanism to reinstate all sanctions in response to an Iranian nuclear violation, as stipulated in the original agreement.70 Iran has already committed multiple violations to justify such a move.
The neutering of the IAEA is further undermining Washington's ability to hold Iran to account. The IAEA has already halted its investigation of Iran's development of uranium metal. Three other files relevant to illicit nuclear activity await Iranian explanations that will probably not materialize. If Washington and Tehran reach a new agreement, the likelihood that the IAEA will press for answers on other possible Iranian nuclear violations seems even more remote. The United States should wield its economic leverage to require the regime to come clean on its past activities.
Only one part of the 2015 agreement deals with the regime's development of a weapon system: Section T of Annex I. However, Israeli officials believe there is a 2015 side agreement between the Russians, the Iranians, and the United States not to enforce this section. Other side agreements may have found their way into the recent talks in Vienna, further undermining the leverage needed to hold the regime to account.
Most obviously, the lifting of sanctions will erode what remains of U.S. and Western leverage to pressure the regime to end its nuclear ambitions. This was a fatal flaw of the last agreement, and complicates the deal currently being negotiated.
A Bipartisan Opportunity
Earlier this year, 165 House Republicans published a letter to President Biden vowing that a new deal would meet the same fate as the JCPOA if he fails to secure congressional support pursuant to the Iran Nuclear Agreement Review Act.71 This law, passed in May 2015, requires the president to submit any deal to the House and Senate for approval. Forty-nine out of 50 Republican senators issued a similar warning in another letter.72
In light of Iran's continued intransigence, Democrats and Republicans should be able to agree that further concessions are a bad idea. Skeptical Democrats should deliver the message to the White House that capitulating to Iran is extremely dangerous.
The Head of the Octopus
Israel, for its part, is expected to intensify its asymmetric campaign, enlisting the integrated tools and skills of multiple Israeli agencies to weaken Iran in the economic, diplomatic, military, political, cyber, and legal arenas. The message from Jerusalem to Tehran has been blunt: Gone are the days when the "head of the octopus" remained untouched while the regime's terrorist tentacles destabilized the Middle East.73 Israel's decision to strike Iran at home, as opposed to merely batting its proxies, was a shift first articulated in former Prime Minister Benjamin Netanyahu's 2018 updated National Security Strategy. The essence of the strategy has since been embraced by Netanyahu's successors, Prime Ministers Naftali Bennett and Yair Lapid.74
The Israeli campaign also includes efforts to inform the international public, primarily in the United States, about the dangers posed by a nuclear Iran. That campaign has a long way to go from Israel's perspective. The American people largely do not understand that a nuclear-armed Iran could soon pose a threat to the United States once the regime acquires intercontinental ballistic missiles.
Renewed talks and side negotiations in Vienna present Washington with a stark choice. It can acquiesce to the regime's demands and empower a terrorist state with nuclear ambitions. Or it can devise a joint plan with Israel and other Middle Eastern allies to push Iran to embrace a new and completely comprehensive agreement. The goal must be to permanently and verifiably block the regime's path to a nuclear weapon. Such a deal would restore American and IAEA credibility in the region while preventing a slide toward war.
Brigadier General (Res.) Jacob Nagel is a senior fellow at the Foundation for Defense of Democracies (FDD) and a visiting professor at the Technion Aerospace Faculty. He previously served as acting national security adviser to Prime Minister Benjamin Netanyahu and as head of Israel's National Security Council. Jonathan Schanzer is senior vice president for research at FDD and a former terrorism finance analyst at the U.S. Department of the Treasury.