By Anurag Mishra (US Team) and Martina Ferraresi (Iran Team)
Introduction
Divergent foreign policy philosophies have produced recurring patterns in US policy toward Iran since 2001. Rather than tracing a single ideological arc, three analytical drivers - security imperatives, economic instruments, and alliance commitments - better explain the continuities and ruptures across administrations, revealing why engagement and confrontation have repeatedly alternated without resolving the underlying strategic dilemma.
Security: The Nuclear File and the Proxy Threatย
In 2002,ย President Bushย labelled Iran part of the โAxis of Evilโ over its nuclear program. Aย 2007 US National Intelligence Estimateย found Iran had likely halted covert weaponisation by 2003, followed byย 2006 UN sanctions. Diplomacy under President Obama produced theย JCPOAย in 2015, restricting Iranโs program in exchange for sanctions relief.ย President Trumpย withdrew the US from the agreements in 2018, despite the IAEAโs verified Iranian compliance; by July 2019, Iran breached its limits on its stockpile of low-enriched uranium, going beyond theย JCPOAโs cap.ย President Bidenโsย Vienna talks in 2021 stalled by 2022, with sanctions remaining in place. Iran began enriching toย 60%, reaching roughlyย 3,800ย kg by August 2022, with experts warning that it contained sufficient fissile material for at least one nuclear device, although weaponisation would require additional technical steps.
Furthermore, Iranโs strategic doctrine relies deeply onย proxy warfareย through the โAxis of Resistanceโ, a decentralised network including Hezbollah, Hamas, the Houthis, and Shiสฟa militias. Rather than deploying its own forces directly,ย Iranchannels weapons, training, and funding through the IRGCโs Quds Force, often via Hezbollah, to partners whose local agendas align with Tehranโs goal of pressuring Saudi Arabia, Israel, and the US. This asymmetric architecture lets each actor pursue its own interests while serving Iranian power at low cost. Theย 2020 killingย of Quds Force commanderย Qassem Soleimaniย struck this networkโs operational core but did not dismantle it: after Hamasโs October 7, 2023, attack, the entire axis mobilised in coordination, closing what little remained of any diplomatic window and locking the region into a new cycle of escalation.
Economy: Sanctions as Strategyย
Sanctions have functioned as the USโs primary lever of coercive diplomacy against Iranโs nuclear program. In July 2010, Congress passed CISADA, marking the shift from targeted export controls to systemic financial warfare. The meaning of CISADA was to sanction foreign banks and companies for doing business with Iranโs energy sector or sanctioned Iranian entities, effectively forcing them to choose between access to Iran and access to the US financial system. The EU further escalated pressure in 2012 with an oil embargo, banning imports of Iranian petroleum products, sanctioning Iranโs energy, financial, and transport sectors, and freezing the Central Bank of Iranโs assets. Subsequently, Iranian banks were expelled from SWIFT, cutting Iran off from international banking and severely constraining its ability to sell oil or access hard currency. After withdrawing from the JCPOA in 2018, Trump launched his first โMaximum Pressureโ campaign, reimposing sanctions on Iranโs energy, shipping, and financial sectors and designating the IRGC a Foreign Terrorist Organisation. In February 2025, Trump reinstated the campaign, aiming to drive Iranโs oil exports to zero, with the stated goal of making Iranโs economy collapse by shutting down its oil sector.
Alliances: Israel, the Gulf, and Europe
Israel
Israel has shifted from a proxy war to a direct engagement with Iran. In April and October of 2024, the two nations faced direct state-to-state strikes that broke the decades-old tradition of โshadow warโ, and Israel launched an open-air war on Iranโs nuclear and military infrastructure in June 2025, dubbed the Twelve-Day War, that included a one-off US strike on Fordow, Natanz and Isfahan, before a ceasefire took effect on June 24, 2025. Israelโs air power has been widely assessed to have weakened, but not destroyed, Iranโs nuclear program, which is why American bunker-buster bombs were reportedly needed to strike the deeply buried Fordow facility. This delicate balance was once again upset in February 2026, when on February 28 joint US-Israeli missile attack launched against Iranโs military struck senior Iranian military officials, including Supreme Leader Ali Khamenei, and initiated five weeks of regional conflict that ended with a ceasefire agreement on April 7-8, 2026, which was followed by a formal memorandum ending the conflict signed by Presidents Trump and Pezeshkian on June 17, 2026. Washingtonโs relationship with Israel appears to have moved from arms sales and diplomatic backing toward something closer to direct co-belligerency, which many read as a strong signal that for Washington and Israel, a nuclear-armed Iran is treated as a red line rather than mere rhetoric.
Arab / Gulf Partners
The Gulf countries have been hedging rather than aligning themselves. Riyadhโs 2023 Chinese-brokered deal with Tehran signalled a willingness to reduce risks as opposed to confronting Tehran, but Israelโs air strike on Hamas leaders in Doha over a US ally that hosted a US air base complicated existing doubts about the USโs security guarantees in the Gulf region. The Saudi-Pakistan Strategic Mutual Defense Agreement of September 17, 2025 was signed by the two nations, both of which agreed to consider an attack on one as an attack on the other, and was widely interpreted not only as a hedge against an uncertain Washington, but also against an unchecked Israel as well. Some have suggested the deal could extend a nuclear umbrella to Saudi Arabia, although analysts caution against reading it as a formal war guarantee. Analysts have also pointed out that the agreement may lead to a new UAE-India defence cooperation, adding another layer to the Gulf security architecture, but not necessarily replacing it. The net result is a Gulf that is apparently diversifying its security guarantors, while staying formally in the US orbit.

European Allies
Through the JCPOA, Europe has primarily exercised its influence through diplomacy, sanctions, and multilateral institutions rather than military means. Following years of patience, France, Germany and the UK applied theย โsnapbackโย mechanism of the JCPOA on 28 August 2025, overย Iranโs repeated failure to complyย with its nuclear obligations, including the production of highly enriched uranium without any apparent civilian purpose. The E3 said the enriched-uranium stockpile in Iran was about 48 times the limit imposed by the JCPOA and that there are ten โsignificant quantitiesโ of highly enriched uranium in Iran. Sanctions that had been lifted under the 2015 deal were therefore restored, and by the end of September 2025, the EU also reimposed its own nuclear sanctions, such as asset freezes and travel bans. At the time, Russia and China argued the E3 lacked a legal mandate to trigger a snapback, as the Security Councilโs authority over the file had expiredย -ย and did so until the Council split over the issue along the same lines it has before. So, now, Europeโs role in Washingtonโs alliance is more about legal and multilateral legitimacy than military readiness: the E3 provided a UN Security Council seal of approval on Iranโs isolation that the unilateral US sanctions could not.
Conclusion
Security considerations remain the unalterable policy of the United States government, and, regardless of the differences in administration temperament over the course of four different administrations, no administration appears to have accepted a nuclear-armed Iran as a tolerable outcome. By 2025-26, this red line was enforced not only through sanctions but also through direct military strikes against Iranian nuclear infrastructure and leadership - a shift that many analysts see as marking a new phase in US policy. However, its long-term durability remains to be seen.
Alliance commitments have been fulfilled on paper, but not in practice. Israelโs evolution from an โactiveโ to a โco-belligerentโ has drawn the US-Israel relationship closer, while also placing strain on US relations with the Gulf states.Among these, Saudi Arabia appears to be leading efforts to diversify its security architecture, notably through its agreement with Pakistan, with a possible parallel arrangement with the UAE reportedly under discussion. Meanwhile, European allies have shown that legal and multilateral instruments can still carry weight even without direct US military backing, having reinstated UN sanctions in a context where unilateral US measures could not achieve the same effect.
The economic sanctions are the most flexible instrument in the policy toolkit, however - reversible, calibrated and renewable - and there is room to manoeuvre towards negotiations even after the outbreak of military conflict, provided that Tehranโs nuclear ambitions are kept in check.
What has been most important in the evolution of US Iran policy since 2001 is this asymmetry: rigid security boundaries, malleable economic measures and more and more varied rather than monolithic alliance pledges.














