A “Good Deal” with Iran? Requirements for Preventing a Future Nuclear Breakout

For more than two decades, international diplomacy toward Iran has been guided by the objective of preventing the regime from acquiring a military nuclear capability. Although this objective remains valid, Tehran’s demonstrated capabilities have fundamentally changed the strategic context for any new diplomatic efforts on this issue. For one, the regime’s direct ballistic missile attacks against Israeli civilian populations demonstrate that its missile program is not a theoretical adjunct to its nuclear ambitions, but an operational instrument of military and political coercion. Therefore, any new agreement cannot simply slow down Iran’s nuclear progress and extend hypothetical breakout timelines—it must structurally and irreversibly prevent the possibility of a rapid nuclear breakout, in part by constraining efforts to integrate nuclear activities with missile development work.

Objectives and Scope of Negotiations

A central policy question for the United States is whether renewed talks should be confined to nuclear activities or expanded to include Iran’s missile advancements, regional proxy sponsorship, brutal repressive apparatus, and so forth. Answering this question raises a dilemma: Tehran would likely reject any substantial constraints in these domains, yet excluding them from negotiations would be tantamount to perpetuating a major blind spot in allied strategy on Iran. Rather than attempting to resolve this broader dilemma, the guidelines below focus solely on the required terms for an effective nuclear deal, but with one important addendum: the inclusion of serious missile-related provisions tied to nuclear integration and weapons delivery.

In general terms, eliminating Iran’s capacity for rapid nuclear breakout and weaponization would require durable structural constraints, intrusive and continuous verification mechanisms, and the removal of technological pathways enabling rapid escalation from civilian to military nuclear capabilities. A key lesson of the past two decades is that there is no room for leniency when it comes to restricting Iran’s nuclear activities. Timeframes that appeared to be long in previous agreements like the 2015 Joint Comprehensive Plan of Action (JCPOA) later proved to be strategically short—in part because of major policy changes between U.S. administrations, though many observers argued that the original terms of that deal would have been too short even if they had been permitted to run their full course. 

Whatever the case, the result is that Iran was able to preserve vital nuclear know-how, develop advanced centrifuges for faster uranium enrichment, and maintain its future breakout options—capabilities that were significantly harmed but only partially set back by U.S. and Israeli military strikes against the program’s infrastructure. At the same time, prolonged European hesitation on activating the “snapback” mechanism for UN nuclear sanctions effectively rendered them irrelevant. A future framework must therefore be based on structural prevention rather than optional political enforcement or assumptions that the Islamic Republic will moderate.

Requirements for the Next Nuclear Framework

• Much longer time horizon. One of the JCPOA’s most serious flaws was that it embraced the idea of creating legally sanctioned pathways toward an industrial-scale nuclear capability—and much sooner than many observers felt was warranted given the nature and foreign-policy posture of the Iranian regime. Any future arrangement must have far longer terms: at least fifty years, and without short sunset clauses that would enable Tehran’s nuclear program to gain legitimacy and rebuild its full capabilities within a decade.
• No advanced centrifuges. Over time, Iran’s largely permitted progress on advanced centrifuge technology opened its most direct path to rapid breakout. A future framework must therefore include an absolute prohibition on the production, operation, or storage of advanced centrifuges—not just hypothetical future models, but also Iran’s existing IR-2, IR-4, IR-6, and IR-8 models. This prohibition must be enforced for the much longer timeframe discussed above, and must include full dismantlement of related industrial infrastructure, component manufacturing facilities, and procurement networks.
• Absolute prohibition against research and development on enrichment. To prevent a latent breakout capacity, Iran must be barred from conducting R&D on enrichment and fuel-cycle technologies for the duration of the (longer) agreement, including experimental cascades, pilot enrichment facilities, and simulations. This prohibition should extend to universities and research institutes (see the verification discussion below for how this might be enforced).
• Zero or capped enrichment and stockpiles. The preferred standard is that no enrichment should be conducted on Iranian territory for the duration of the deal—whatever limited amounts of nuclear fuel the country may require for future civil needs should be supplied externally. If this proves politically unattainable, however, enrichment could be capped at low levels under continuous international supervision, with stockpiles of fissile material kept far beneath the breakout threshold and any excess materials subject to mandatory export. (The exact stockpile limits would have to be discussed at the technical level; for more on such matters, see The Washington Institute’s Iran Nuclear Glossary.)
• Closure of critical facilities. Certain nuclear facilities are intrinsically incompatible with a breakout-proof framework and must be permanently disabled, including any sites constructed a certain distance underground. (The exact distance would be determined by negotiators based on expert assessments.) Permanent dismantlement and sealing must be part of this process.
• Continuous, intrusive verification regime. Verification of Iran’s future nuclear activities must exceed traditional arms-control monitoring and approach counterproliferation transparency standards. In practice, this entails continuous monitoring by the International Atomic Energy Agency (IAEA); monitoring of academic institutions, scientists, supply chains, and facilities involved in centrifuge production and assembly (with methods and other specifics to be determined by the negotiators); no-notice access for inspectors; interviews with Iranian nuclear personnel as needed; and real-time remote digital monitoring. Most of these elements were included in the JCPOA, so negotiators should place extra emphasis on the two new provisions: no-notice access, and real-time remote monitoring by IAEA personnel located abroad, both of which Tehran opposed during the 2015 talks.
• No integration between missile and nuclear work. A breakout-proof framework must include oversight of all activities that might enable integration between missile technologies and a military nuclear program. Warhead-related experiments, hydrodynamic simulations, and nuclear weapons computational modeling should be prohibited, as should the acquisition of any items that could support militarization or weaponization (e.g., see sections 5 and 6 of the “Guidelines for Transfers of Nuclear-Related Dual-Use Equipment” issued by the Nuclear Suppliers Group, which include very wide definitions of restricted items). In addition, a comprehensive ban on intercontinental ballistic missile (ICBM) development must be imposed given the direct relevance of this capability to U.S. and European homeland security and the likelihood that Iran could attain it within a few years absent new constraints.
• Graduated, reversible nuclear sanctions architecture. A new agreement must be embedded in a sanctions system that conditions any economic relief granted to Iran on continuous, verifiable compliance. Broad removal of sanctions on certain entities—particularly the Islamic Revolutionary Guard Corps (IRGC)—should be avoided absent proven structural dismantlement of nuclear and missile infrastructure. Energy export ceilings should likewise be established with conditional, incremental expansion, and any Iranian access to the Western financial system (including the SWIFT network) should be limited and reversible. Notably, if the next deal focuses exclusively on nuclear issues, then sanctions relief should follow suit—that is, Iranian officials should understand that the many other sanctions and designations levied against the regime for terrorist activities, human rights violations, money laundering, and so forth would necessarily be left in place, and foreign banks and other private institutions would react accordingly.

Feasibility vs. Strategic Sufficiency

The above framework reflects what would be strategically sufficient to prevent an Iranian nuclear breakout, not what Tehran is likely to accept. Regardless of diplomatic feasibility, however, one thing is clear: any agreement that falls short of these structural constraints may delay a breakout but would not prevent it, thereby replicating the JCPOA’s core deficiencies. 

A “good deal” with Iran should not be defined by diplomatic optics or short-term de-escalation; it should be defined by whether it permanently removes the regime’s ability to transition rapidly from civilian nuclear activities to a military nuclear capability. This definition necessarily includes constraints on any Iranian missile activities that might facilitate nuclear coercion. An agreement that fails to meet these definitions would risk giving Tehran the time, legitimacy, and technological progression it needs to attain a military nuclear capability down the road.

Zohar Palti is the Viterbi International Fellow with The Washington Institute. Previously, he served as head of the Mossad Intelligence Directorate and head of the Policy and Political-Military Bureau at Israel’s Ministry of Defense.