Iran's approach to nuclear weapons may have been its most consequential strategic error. For years, Tehran pursued a threshold strategy - building the technical infrastructure and know-how to produce a bomb without actually crossing the line. The 2015 nuclear deal, known as the JCPOA, was supposed to freeze this ambiguity in place by exchanging restrictions for sanctions relief.

The JCPOA was "paradoxically, the beginning of Iran's undoing," Nicole Grajewski and Ankit Panda of the Carnegie Endowment for International Peace have argued in Foreign Affairs, as "Hvylya" reports.

Under the deal's monitoring provisions, Iran opened its nuclear facilities to International Atomic Energy Agency inspectors, whose regular reports detailed centrifuge numbers by hall, exact enrichment levels and stockpile quantities. When the first Trump administration pulled out of the agreement in 2018 and reimposed sanctions, Iran had already surrendered valuable intelligence about its program - and received little lasting benefit in return.

Tehran then compounded the error. After exiting the deal itself, Iran began publicly announcing enrichment breakthroughs, new centrifuge types and growing stockpile sizes. By early 2025, it could theoretically produce enough weapons-grade uranium for a single device in under a week and possessed enough material for roughly nine or ten weapons if enriched slightly further. Iran was, as the authors note, the nonnuclear state closest to acquiring the bomb.

But two pathways protect a near-nuclear state, Grajewski and Panda argue: ambiguity about its capabilities, or speed - building a weapon so quickly that adversaries cannot organize a preemptive strike. Iran chose neither. It relinquished opacity through the JCPOA's inspections and then broadcast its subsequent advances, giving the U.S. and Israel confidence they knew exactly what they were striking. North Korea, by contrast, rushed to test a device before the world could respond - and has remained untouchable since.

The Carnegie scholars conclude that Iran's mistake was not getting close to a bomb. It was letting everyone watch.

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