The US ceasefire agreement with Iran has presented Israel's prime minister with a political nightmare, smashing the three cornerstones of Benjamin Netanyahu's political career, and leaving him trapped in a new security dilemma.

How can the man who styled himself as the political whisperer of Washington, with real influence over American politicians, be sidelined quite so comprehensively and insulted so publicly by his key US ally?

How can the man who made taking on Iran the centre-piece of Israel's security policy end the war with Iran arguably in a stronger position?

And how can his old, tarnished political image as Israel's "Mr Security" survive the demand from Washington and Tehran that Israel cease attacking Hezbollah in Lebanon, months before an Israeli general election?

The options facing Netanyahu now are not good. They were summarised by the opposition leader, Yair Lapid, in the Knesset on Monday as "either a direct and destructive confrontation with our greatest ally, or a submissive surrender of Israeli interests".

The expletive-laden assessment by US President Donald Trump that Netanyahu showed no judgement when ordering a strike on Beirut on Sunday has been seized upon by his political rivals and media commentators, already focused on the election that must be held before the end of October.

But comments from members of Netanyahu's own Likud party, and far-right cabinet ministers in his governing coalition, also show the pressure he faces from his own side - most sharply over the demand from Tehran that the ceasefire covers "military operations on all fronts, including Lebanon".

"Trump's agreement does not bind us," Israel's far-right national security minister, Itamar Ben-Gvir, wrote on social media on Monday. "We are not partners to this agreement that does not ensure our security."

"Israel will continue to protect itself," Likud lawmaker Ariel Kallner told me, though he would not clarify whether that meant Israel would continue its attacks.

"We will do what we need to do. And we expect our friends to understand us," he said. "Sometimes there are disagreements between allies, and allies should also understand their allies when they are in danger."

Sima Shine, a former Mossad official and Iran specialist said: "It's difficult to understand why the Americans accepted it.

"By allowing Iran to decide what will happen in Lebanon, the US is giving Iran the possibility to continue to support Hezbollah, and to make sure that Hezbollah is a major political actor in the Lebanese arena.

"Israel is not happy with that – neither the security establishment, nor the political," she said.

Amid the cacophony of criticism and outrage from across the political spectrum, Israel's prime minister himself has so far been absent. Often quick to claim victory, his silence now has been read by some as a sign of the difficulty he faces in deciding his next steps.

Security has been the cornerstone of Netanyahu's offering to voters for decades. That is an increasingly difficult message to deliver.

His response to the devastating Hamas-led attacks on 7 October 2023 was to shift Israel's security policy to a more aggressive approach – pre-empting threats rather than containing them.

Changing the Middle East by removing the threats Israel faced was his solution to that crisis.

But even though Israeli forces have demolished much of Gaza and killed more than 73,000 people, according to the Hamas-run health ministry, Hamas is still in control of half the territory and reasserting its power there, while a US-brokered peace plan and a US-appointed administration for Gaza remain stuck in limbo, eight months after Israel and Hamas agreed a ceasefire.

Netanyahu's new approach to security has left Israeli forces occupying large areas of Gaza, Lebanon and Syria. That's popular with many Israelis and unlikely to end before the election, but is also stretching Israel's military resources and reservists to breaking point, with no clear diplomatic pathway out.

Repeated rounds of conflict with Hezbollah and the Iranian regime have not eliminated Israel's key enemies, but left Tehran in the hands of more hardline leaders, with less fear of US-Israeli might, and greater leverage through the Strait of Hormuz.

Now Israel's arch-enemy appears to be the one with influence over Israel's key ally.

"Israel's failure requires a renewed assessment of its strategy towards Tehran. [It] must formulate more realistic and restrained priorities," according to Danny Citrinowicz, a senior Iran researcher at Israel's Institute for National Security Studies (INSS).

"Any Israeli military move perceived in Washington as an attempt to sabotage the agreement is expected to encounter a harsh response from the US, he said in an article for the daily newspaper Israel Hayom.

"Unlike during the Obama administration, when Benjamin Netanyahu could try to bypass the White House by mobilising support in Congress and in US public opinion, those options barely exist at this time."

Netanyahu's pitch to Israeli voters has long been that his policies and political skills are the best protection from regional threats; that promise looks increasingly overtaken by events.

Regime change in Iran might have rescued his political image and his election narrative. Instead, his new security approach has left him facing the choice of confrontation or surrender, not with an enemy, but with an ally.