The US-Iran conflict and the mutual blockade of the Strait of Hormuz have upended decades of diplomatic stalemate, but may also have created an unexpected opening for a lasting deal. In this Policy Insight, Simon Johnson and Amir Kermani analyse why previous agreements, including the JCPOA, were always vulnerable to collapse: a structural "time inconsistency" problem means any US administration has an incentive to reimpose sanctions once Iran has surrendered its nuclear leverage. The authors