The United States and Iran signed a Memorandum of Understanding in June 2026 intended to end the conflict and negotiate a broader settlement. Within weeks, the framework was dead: after commercial tankers began using a southern route to transit the Strait of Hormuz close to Omani territorial waters, Iran started attacking the vessels, and the United States launched its first post-MoU strikes on June 26.
The collapse confirmed the warning analysts had issued when the ceasefire first held in April: without a political settlement, military pauses in this war function as rearmament windows.
The June Precedent
The resumption followed a violent June. On June 9 and 10, US forces launched waves of strikes on multiple Iranian targets, firing 49 Tomahawk missiles in one operation, after the downing of an Army helicopter and what President Trump described as slow progress in negotiations. Iran struck US bases in Jordan, Kuwait and Bahrain in response.
Where It Leaves Diplomacy
Both sides have now demonstrated the ability to escalate and to talk, sometimes in the same week. The MoU's failure shifts the burden to regional mediators, whose channels have carried every deal so far; and to a US Congress that has yet to pass an authorization for a war entering its fifth month.
