Abstract:

On 17 June 2026, the United States and Iran signed a fourteen-point memorandum of understanding intended to end the war that began on 28 February. Article 1 of that memorandum stated that ending the war in Lebanon was an integral part of the broader ceasefire. Iran had made a halt to Israeli operations in Lebanon its central precondition for any lasting settlement. But Israel was not a party to the memorandum, and Israel continued to strike Lebanon throughout the period of the talks, killing dozens of people in the days around the signing. Iran, bound by its own precondition, was forced either to respond to the Lebanon strikes and be blamed for breaking the ceasefire, or to absorb them and watch its central demand ignored. This article argues that the structure of the arrangement was the mechanism of its failure. The party with the greatest interest in continuing the war was the one party not bound by the agreement to end it, and it retained, throughout, the ability to collapse the ceasefire through Lebanon without ever being a signatory who could be accused of violating it. The finding is that the war resumed not because Iran and the United States could not agree, but because the agreement did not bind the state that wanted the war to continue.

Main Article:

An agreement to end a war can only be kept by those who sign it. This is obvious, and it is precisely the fact that the structure of the 2026 ceasefire was built to obscure. When the party most invested in the continuation of a war is left outside the agreement to end it, the agreement acquires a flaw that no amount of good faith among the signatories can repair. It can be collapsed at will by the one actor who never promised to keep it.

That is the story of the ceasefire between the United States and Iran, and it is the key to understanding why a war that both signatories had agreed in writing to end is being fought again five months later.

Begin with what the memorandum actually said, because its first clause contains the whole problem.

On 17 June 2026, the United States and Iran signed a fourteen-point memorandum of understanding, mediated by Pakistan and Qatar, intended to end the war that had begun on 28 February with the American and Israeli strikes that killed the Iranian Supreme Leader. According to the House of Commons Library of the United Kingdom, Article 1 of that memorandum provided for the permanent termination of military operations on all fronts, and it explicitly included the conflict between Israel and Hezbollah in Lebanon. Al Jazeera confirmed that Article 1 of the MOU explicitly states that ending the war in Lebanon is an integral part of the broader ceasefire. [1] [2]

This was not an incidental provision. It was the load-bearing one. Iran had stated consistently, since the first pause in April, that a halt to Israeli operations in Lebanon was its precondition for any lasting end to the war. President Pezeshkian had named it among Iran's conditions. Iranian negotiators had repeated it through every round. The end of the Lebanon war was the clause on which Iran's signature depended. [1]

Now observe who was not bound by that clause.

The House of Commons Library notes, in describing Article 1, that neither Hezbollah nor the Lebanese government were party to the memorandum or the talks. And neither was Israel. The memorandum was signed by the United States and Iran. The state conducting the military operations in Lebanon that Article 1 was written to stop had signed nothing. [1]

The consequence followed with the inevitability of a designed mechanism.

Israel continued to strike Lebanon throughout the period of the talks. Britannica records that despite the ceasefire, the Israel Defense Forces had continued to strike targets in southern Lebanon almost daily, and that renewed Israeli strikes in the Beirut area on 14 June prompted Iran to prepare a response, which only direct American intervention prevented, so that the memorandum could move forward. [3] Al Jazeera reported that in the days around the signing, Israeli strikes in Lebanon killed dozens of people, including an air strike on the southern village of Qennarit on 20 June, even as American and Iranian representatives prepared to meet in Switzerland to cement the truce. [2]

Consider the position this created for Iran, because it was an impossible one, and its impossibility was the point.

Iran had signed an agreement whose first article required the Lebanon war to end. The Lebanon war did not end, because the party fighting it had not signed the agreement. Iran therefore faced a choice with no good option. It could respond to the continued Israeli strikes on Lebanon, honouring the precondition it had fought for, and be accused by the United States of breaking the ceasefire it had just signed. Or it could absorb the strikes, holding to the ceasefire, and watch the central demand for which it had signed be violated daily with no recourse. Either it broke the deal by defending its precondition, or it kept the deal by abandoning it.

When Israel struck southern Beirut on 7 June, days after a ceasefire in the Lebanon conflict, Iran launched ballistic missiles toward Israel, the first direct exchange since April, and Israel retaliated. [3] Netanyahu then said that Iran had tried to create a new equation by linking Lebanon to the Iranian response. [4] But the linkage was not an Iranian invention. It was Article 1 of the memorandum the United States had signed. Iran was being accused of manufacturing a connection that the agreement itself had made explicit. The signatory was blamed for enforcing the text against the non-signatory who was violating it.

This is the mechanism, stated plainly. Israel could collapse the ceasefire without breaking it, because it had never signed it. Every strike on Lebanon placed Iran in violation of a clause Iran was trying to uphold. The state that wanted the war to continue held a permanent instrument for continuing it, and that instrument was its own exclusion from the agreement to stop.

Why the United States accepted an arrangement structured to fail on behalf of a party it was not obligated to serve is the question that opens onto the deeper matter. Because the United States did not merely tolerate the Israeli strikes that were collapsing the agreement it had signed. It protected the space for them. When Iran prepared to respond to the 14 June strikes on Beirut, it was American intervention that prevented the Iranian retaliation, not to preserve the ceasefire by restraining Israel, but to restrain Iran while Israel continued. [3] The signatory power used its leverage on the party keeping the agreement rather than on the party outside it. Washington held Iran to a deal that Israel was permitted to unravel.

And here the analysis arrives at the fact that names the entire structure, because the beneficiary of the arrangement has described it out loud. The Israeli finance minister, one of those who lobbied for the war, stated in July that Israel has no interest in joining the campaign against Iran because the current situation is the best for Israel. Israel opposed the June memorandum, worked against it, and having helped ensure its collapse, now declares that the ideal condition is the one in which the United States fights the war and Israel does not. [2]

Assemble the sequence and the design is complete. Israel wanted the war. Israel was not made a party to the agreement to end the war. Israel continued the Lebanon strikes that the agreement's first article prohibited. Those strikes forced Iran into the position of either breaking the ceasefire or surrendering its precondition. The United States restrained Iran rather than Israel. The ceasefire collapsed. The war resumed. And the state whose conduct collapsed it now announces that it wants no part of the fighting, because the resumption it engineered has produced the outcome it prefers: America at war with Iran, and Israel at rest.

This reframes every question about the ceasefire that is usually asked in isolation.

When it is asked why Iran refuses a ceasefire, the answer is not that Iran rejects peace. Iran signed the peace. Iran refuses a ceasefire that permits the Lebanon strikes to continue, because it has already seen that such a ceasefire binds only Iran while leaving the actual fighting untouched. Iran wants a permanent end because it has learned what a temporary one is worth: a document that constrains the signatory and frees the party outside it.

When it is asked why the United States cannot simply end the war, the answer is that ending the war permanently is not entirely America's to decide, because the continuation of the war does not depend on American choices alone. As long as Israel can strike Lebanon and thereby trigger the sequence that collapses any agreement, the United States cannot deliver the permanent termination its own memorandum promised, because it does not control the party that holds the trigger.

And when it is asked who is destroying what, and to what end, the ledger acquires its meaning from the structure. The United States strikes Iranian military and air-defence sites. Iran strikes American bases, missile systems, radars and Gulf facilities. Iran is raising the cost on the party that is present and paying, the United States, in order to force an end to the war. But the party that wanted the war and benefits from it, Israel, is absent from the ledger entirely. It takes no strikes because it is fighting no war. Iran is applying pressure to the address that signed the agreement, while the address that broke it receives no pressure at all, because it removed itself from the arrangement before the pressure began. Iran is pushing, with full force, on the wrong door, because the party it most needs to move is the one that arranged not to be in the room.

The ceasefire did not fail because peace was impossible between the United States and Iran. They wrote peace down and signed it. It failed because the agreement to end the war did not bind the state that wanted the war to continue, and that state kept the one instrument, the Lebanon strikes, that could collapse the agreement without ever appearing to violate it. A ceasefire that excludes the most committed belligerent is not a fragile peace. It is a war with a signing ceremony in the middle of it, and the resumption was not a breakdown of the design. It was the design.

References:
1. House of Commons Library, United Kingdom. "US-Iran Ceasefire and Nuclear Talks in 2026." 2026. Citing the 17 June signing of the fourteen-point memorandum of understanding, Article 1 providing for the permanent termination of military operations on all fronts including Israel and Hezbollah in Lebanon, the fact that neither Hezbollah nor the Lebanese government nor Israel were party to the memorandum, and the Iranian conditions stated by President Pezeshkian.
2. Al Jazeera. "Israeli Attacks Kill Dozens in Lebanon as US, Iran to Hold Talks on Truce." June 20, 2026. Citing Article 1 of the MOU making the end of the Lebanon war an integral part of the broader ceasefire, the Israeli strikes killing dozens including the strike on Qennarit on 20 June, and the Burgenstock talks. Also Al Jazeera and CNN reporting of July 21, 2026 on the statement of Finance Minister Bezalel Smotrich that the current situation is the best for Israel.
3. Encyclopaedia Britannica. "2026 Iran War." 2026. Citing the near-daily IDF strikes on southern Lebanon despite the ceasefire, the 7 June Beirut strike and the resulting first direct Iran-Israel exchange since April, and the 14 June Beirut strikes that prompted an Iranian response prevented only by US intervention so the memorandum could move forward.
4. CNN. "Ceasefire Falters as Israel and Iran Trade Worst Strikes in Months." June 7-8, 2026. Citing the Israeli strike on southern Lebanon less than an hour after Iran suspended operations, and Netanyahu's statement that Iran had tried to create a new equation by linking Lebanon to the Iranian response.