How We Ended Up Here: A Post-Mortem of the Iran Deal

How scrapping the JCPOA led to an unnecessary and costly war

President Donald J Trump spent the better part of a decade telling the world that Barack Obama’s (among many others) Iran deal was the worst agreement in American diplomatic history. Iran’s nuclear program reached its most advanced state ever.

He launched a war that killed thousands, shut off a fifth of the world’s oil supply, and ended with a ceasefire built on terms that are, by every objective measure, more generous to Tehran than anything Obama or the EU secured. This is how that happened, and what the legal wreckage left behind tells us about the remaining integrity of the rules-based international order.

Three things are worth setting out from the start. Firstly, the JCPOA — the “Joint Comprehensive Plan Of Action” — was working when Trump killed it. Second, abandoning it accelerated the very nuclear threat it was designed to contain. Third, the diplomacy that preceded the February 2026 war may have been on the verge of a breakthrough when the bombs fell. The case that follows is built on public record.

What Obama Helped Build

The JCPOA was signed in Vienna on 14 July 2015 by Iran, the United States, the United Kingdom, the EU, Russia, and China. It was not a bilateral deal between Washington and Tehran, as Trump has consistently implied. It was a multilateral framework, endorsed by UN Security Council Resolution 2231, which gave it binding force under international law.

Under its terms, Iran agreed to reduce its enriched uranium stockpile by 97 per cent, dismantle two-thirds of its centrifuges, halt its plutonium reactor, and accept the most intrusive international inspection regime in the history of nuclear non-proliferation. In return, Iran received phased and reversible sanctions relief, with a snapback mechanism that allowed full penalties to be reimposed automatically the moment Iran violated any provision.

Trump’s claim that the agreement gave Iran the right to a nuclear weapon has been rated ‘False’ by PolitiFact. The JCPOA was built on Iran’s membership of the Nuclear Non-Proliferation Treaty, which it signed in 1968 and ratified in 1970. That treaty’s prohibition on nuclear weapons for non-nuclear states has no sunset clause, no phase-out, and no expiry. The JCPOA added a concrete, independently verified layer of enforcement on top of it.

Something worth noting is that Trump himself certified to Congress on two separate occasions that Iran was complying with the deal before arbitrarily reversing course.

Maximum Pressure, Minimum Results

On 8 May 2018, Trump announced the US withdrawal from the JCPOA and the reimposition of sweeping sanctions. The theory of maximum pressure was straightforward: economic strangulation would force Iran back to the table on broader terms — covering not just nuclear constraints, but also conventional military capabilities. While internally consistent as a theory of coercion, it failed the ultimate test, producing the exact outcome it was designed to avert.

Richard Nephew, a senior research scholar at Columbia University who worked on the original JCPOA negotiations, was direct. Trump’s withdrawal “had a significant accelerating effect” on Iran’s nuclear program. Within a year of the US exit, Iran had exceeded the JCPOA’s stockpile limits. By 2023, it was enriching uranium to 60 per cent purity — a level the IAEA said had no credible civilian justification. Maximum pressure removed the last effective external constraint on the one thing it was supposed to prevent. That is not a side effect. That is the result.

The Biden administration spent years in indirect talks in Vienna attempting to resurrect the deal. Still, those negotiations stalled in part because Iran could not obtain any credible assurance that a future American administration would not simply walk away from whatever was agreed, exactly what the Trump administration had done. This is the obvious lesson of 2018.

The Diplomacy That Was Abandoned

One of the most important — and least covered — facts about the run-up to the February 2026 war is what was actually happening in the final days of negotiations. The Trump administration’s public position was that Iran was not. The record suggests otherwise.

Omani Foreign Minister Sayyid Badr bin Hamad Al Busaidi appeared on CBS’s ‘Face the Nation’ the day before the strikes commenced and stated that Iran had agreed to zero enrichment accumulation and zero enrichment stockpiling, irreversible downgrading of enrichment levels, and full verification. He described this as a significant achievement.

The picture that emerges from the available record is one of a diplomatic process which was not exhausted. The bombs fell not because every avenue had been explored, but because the decision to use force was taken before those doors had closed.

That distinction matters enormously, both legally and historically.

The Cost of the War

On 28 February 2026, the United States and Israel launched coordinated airstrikes on Iran under ‘Operation Epic Fury’. According to the House of Commons Library, the stated objectives included regime change and the elimination of Iran’s nuclear and ballistic missile infrastructure. Iran’s Supreme Leader, Ali Khamenei, was killed in the opening strikes.

The Iranian response was immediate and severe. Missile and drone barrages struck Israel, US military installations across the Gulf, and civilian and military sites in Arab states aligned with Washington. Subsequently, Iran closed the Strait of Hormuz, through which approximately a quarter of the world’s seaborne oil trade and 20 per cent of its liquefied natural gas normally passes.

By March, tanker traffic through the Strait of Hormuz had fallen by 70-95 per cent compared to the pre-war average, with “nearly 800 ships stuck” waiting to pass safely. This resulted in the International Energy Agency taking the unprecedented step to release 400 million barrels from strategic reserves.

The United States justified these strikes under the “inherent right of self-defence”. However, the human cost was substantial and disproportionate.

Iran’s Ministry of Health recorded at least 3,468 killed and more than 26,500 injured, including 7 infants, 376 children and 496 women. The Human Rights Activists in Iran (HRANA, US-based group), cross-referencing government data with local sources, documented 3,636 Iranian deaths — including 1,701 civilians — and noted that military casualties were likely significantly higher. Additionally, the IDF claims that since the start of Operation Roaring Lion, over 6,000 IRGC members have been killed and 15,000 wounded

Lebanon’s Health Ministry reported at least 2,702 killed, with fighting continuing beyond the “ceasefire” as Israel declined to include Hezbollah in its terms. In total, the conflict has resulted in between six and nine thousand deaths across all parties, with tens of thousands injured.

A Pakistan-brokered, two-week ceasefire was announced on 8 April 2026, supposedly extended (as per President Trump). JD Vance described it on the same day as a “fragile truce”. It has been violated by both sides since its declaration.

Over 12,000 deaths, including IRGC personnel. A truly horrific number to witness, increasing over time.

The Art of the Ordeal

For being the man behind “The Art of the Deal”, the dealmaker himself has negotiated nothing tangible or of value so far.

The framing that Donald Trump has applied to Iran’s nuclear program for around a decade rested on a weak proposition: that’s it… Based on the JCPOA being weak, reckless, and so contrary to American interests, that virtually any alternative would be superior.

Yet, the evidence of 2026 has evidently proven those assertions wrong.

Under the JCPOA, Iran dismantled more than 13,000 centrifuges, shipped 98 per cent of its enriched uranium stockpile out of the country, capped enrichment at 3.67 per cent for 15 years, with the Center for International Policy stating “In signing the JCPOA Iran agreed to the most comprehensive and intrusive IAEA weapons inspection system ever negotiated” — commenting on a Department of State publication.

Iran only agreed to these strict measures in exchange for phased, reversible sanctions relief. The arrangement was multilateral, legally grounded in UN Security Council Resolution 2231, and independently verified.

The framework now under negotiation bears little resemblance to those terms. Iran’s ten-point ceasefire proposal, cited by Trump as a “workable basis” for talks, includes the right to continue uranium enrichment, the lifting of all primary and secondary sanctions, an end to all IAEA resolutions against Tehran, war reparations and numerous other demands.

These are the demands of a government that watched the US abandon a working agreement, endured maximum pressure for eight years, weathered two wars, and concluded that its leverage has not been diminished, but rather empowered.

The Carnegie Endowment for International Peace has noted that the Trump administration’s inability to offer sanctions relief, given its own history of walking away from agreements, has made Iran less willing to show flexibility on enrichment.

This is the direct and foreseeable consequence of the 2018 withdrawal. No Iranian government, having watched Washington tear up an iron-clad deal with which Tehran was complying, can reasonably be expected to accept binding commitments in exchange for the illusion of a promise from the US and Israel.

A May 2025 BBC report cited an IAEA assessment that Iran possessed over 400kg of uranium enriched to 60 per cent — a near 50 per cent increase in three months — which can still be used for lower-yield nuclear weapons (requires institution login or subscription to view).

This is a stockpile which did not exist under the JCPOA and has no credible civilian justification. Iran entered the 2026 war as a nuclear threshold state. It is now negotiating its exit as one.

Whatever deal or agreement that eventually emerges will be constructed not from a position of Iranian weakness but one of resilience and perseverance.

Liberalism and the Architecture of Peace

There is a broader dimension to this story that deserves explicit treatment, because it is frequently submerged beneath the operational and diplomatic details.

The JCPOA was, in the most blunt sense, a product of liberal internationalism. It was built on the proposition that states can be bound by rules to which they have consented, that multilateral frameworks are more durable than bilateral or unilateral coercion, and that the mechanisms of international law — including treaty obligations, UN Security Council Resolutions, and independent verification — offer a more reliable path to security than unilateral bullying and hostility.

That proposition had been organising the logic of American foreign policy since 1945, and it had produced the architecture of non-proliferation, free trade, and collective security that the post-war world was built upon.

Analysts of the 2026 war have widely identified the US-Israeli attack on Iran as a departure from the norms of the liberal international order, with some believing that this has fractured the liberal international order. Legal scholars and members of Congress have urged that the strikes were conducted without the statutory authorization that American Law requires. The UN and the UN Human Rights Office of the High Commissioner raised concerns about violations of international humanitarian law by the US, Israel and Iran.

The war was launched during live negotiations, against a state whose Foreign Minister had publicly confirmed that technical talks with the IAEA were continuing and that further discussions had been scheduled.

The rules-based international order is not a piece of architecture that maintains itself. It is sustained by the willingness of its most powerful members to observe its constraints even — and especially — when they possess the capacity to act otherwise. When the US walked away from the JCPOA in 2018, it sent a signal to every state considering a negotiation settlement with Washington that American commitments are contingent on the idiosyncratic preferences and political volatility of the incumbent administration.

As the Carnegie Endowment observed in 2018, the lesson Iran drew from 2018, and that North Korea and others will have drawn from 2026, is that the US is not a reliable treaty partner. This lesson will outlast any ceasefire.

Conclusion: The Wreckage

The case set out at the beginning of this article was a simple one. The JCPOA was working until Trump killed it. Abandoning it accelerated the nuclear threat it was designed to contain. This was foreseeable as a strategic inevitability.

This sequence of escalations suggests a strategic path dependency, where a series of choices are made that systematically foreclose diplomatic exits until military action becomes the only remaining variable. And the diplomacy that preceded the February 2026 war may have been on the verge of a breakthrough in diplomatic relations with Iran.

What has been produced in the JCPOA’s place is a fragile ceasefire, a devastated region, a global fuel and fertilizer crisis whose effects will be felt for years to come, and a negotiating framework in which Iran seems to hold considerably more leverage than it did in 2015.

The administration that spent a decade decrying the ‘worst deal in history’ has arrived at an arrangement that offers fewer constraints, less oversight, and significantly higher Iranian leverage.

The rules-based international order is a set of institutions, norms, and legal frameworks built — in large part — by the US, on the understanding that durable security requires the consent of the governed, the participation of allies, the restraint of the most powerful actors, and critically, adherence to the rule of law. The JCPOA was its application to one of the most dangerous proliferation challenges of the early 21st century. It was a demonstration of what happens when a great power overestimates its capacity to act unilaterally.

The consequences will burden not the administration that made those choices, but the world that must now live and suffer with them.

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DISCLAIMER: This article reflects my perspective as a student. It does not constitute an endorsement or legal opinion, and readers are encouraged to seek professional legal advice for specific issues. Opinions expressed are mine alone and do not bind any future professional obligations, including but not limited to the Bar.

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