There is a particular kind of deal that feels triumphant on the day it is signed and corrosive on every day thereafter. The 14-point memorandum of understanding (MoU) the Trump administration concluded with Iran this week is shaping up to be exactly that species of triumph – the kind that requires applauding quickly, before anyone understands the implications.

Start with what is genuinely credible, because it is real. The president’s campaign on ending a shooting war, not managing one indefinitely, and a negotiated halt to active hostilities – one that reopens the Strait of Hormuz, lifts a naval blockade, and stops the bombing on all sides – is not nothing. Wars that end through exhaustion rather than victory still end, and the alternative to this MoU was not a better deal sitting on the table; it was an open-ended military commitment with no obvious exit. Give credit where it belongs: This administration was willing to use force when diplomacy failed, and willing to negotiate once force had made its point. That sequencing – military pressure first, diplomacy second – is precisely the theory of the case this president has always offered, and on its own terms it is not unreasonable.

But this triumph also has a very obvious shortcoming. The ceasefire was negotiated without the ally that has borne the highest cost for confronting Iran for the past two decades: Israel. The talks ran through Washington, through Pakistani mediators, through Geneva and Versailles – everywhere, it seems, except Israel, the number one United States ally in the region, which has spent years absorbing Hezbollah rockets, Houthi missiles, and the slow bleed of an Iranian proxy network built to destroy it. An ally who supplied the intelligence, the targeting, and in no small part the military rationale for the February attacks on Iran that began this war is now being asked to treat as settled a document it had no hand in drafting. That is not the treatment one extends to a partner. It is the treatment one extends to a complication.

Consider the sequencing that the MOU actually contains, because the details confirm the slight. The asset unfreezing proceeds “in light of the progress of negotiations” – elastic enough to mean almost anything – while verification is pushed off to a “final agreement” still 60 days away, extendable by mutual consent. The leverage moves first, the proof follows later, if at all. Any negotiator who has dealt with Tehran across four decades could tell you which half of that sequence Iran will treat as binding and which half as aspirational.

Then there is the $300bn reconstruction fund – a figure unthinkable from this White House in any other context, defended on the technicality that Washington itself won’t write the cheque. That distinction will not survive contact with reality, and it will least survive contact with an Israeli government watching billions flow towards the regime that arms Hezbollah on its northern border and the Houthis on its southern approaches. The administration that built its critique of the Obama-era deal around the danger of flooding the regime with cash now finds itself the architect of a far larger flood – one Israel will be left to absorb the consequences of, with no seat at the table that decided it.

The nuclear core of the deal compounds the injury. Iran pledges not to “procure or develop” nuclear weapons – a commitment it has made and hollowed out before. The disposition of its enriched-uranium stockpile is left vague, dilution “on-site” rather than removal, with the harder question of enrichment rights kicked to the future. Israel has spent decades treating an Iranian nuclear weapon as the one outcome it cannot survive and will not negotiate around; it is now watching its closest ally accept, on its behalf, a framework no clearer than the one this president once denounced as appeasement.

Then there is Lebanon, folded into the same document as though it were a footnote, where the agreement to end fighting “on all fronts” sits uneasily with an Israeli government that has said plainly it will not withdraw from border areas it considers essential to its security. An American president can sign for the US. He cannot sign for Israel, and asking it to treat a deal struck around it as binding upon it is not diplomacy. It is presumption.

None of this means the alternative – open-ended war – was preferable, or that this president lacks leverage going forward. He has shown Iran that US patience has limits and US power is real. But a serious Iran policy treats Israel as the load-bearing ally it is, not as a stakeholder to be briefed after the fact. The fairest reading is not that the administration set out to sideline its primary ally, but that it allowed expedience – a faster deal, a cleaner signing photo – to crowd out the harder work of negotiating in lockstep with the partner who will live with the consequences longest. There is a defensible case for buying time and using the next 60 days to fold Israel’s red lines back into the process before the final agreement is set. There is no defensible case for treating this interim pause as finished business, while the ally most exposed to Iranian revanchism reads about its terms in the same news cycle as everyone else.

The administration would do well to recall its own most persuasive argument against its predecessor: That vague commitments backed by upfront sanctions relief are a gift to the Iranian regime – and that an agreement which sidelines Israel is not a Middle East peace, but a postponement of the reckoning Israel alone cannot avoid. That critique was correct in 2015. It does not become less correct because the signature belongs to a different president. The president’s supporters, this writer included, owe him candour rather than cover: A deal that leaves US’s most reliable ally on the outside looking in is not strength. It is precisely the kind of arrangement this president was elected to refuse to make.

The views expressed in this article are the author’s own and do not necessarily reflect Al Jazeera’s editorial stance.