Benjamin Netanyahu portrays himself as a leader uniquely able to protect Israel's security and deal effectively with Donald Trump.

But the US president, it seems, takes a very different view of the prime minister's credentials. "Without me there would be no Israel," Trump declared on Tuesday, two days after signing a peace agreement with Iran that showed a cavalier disregard for the security interests of America's supposed ally. "Israel would have been blown up a long time ago, had I not gotten involved."

It was an extraordinary statement not only because Trump was barely two years old when Israel was founded in 1948, but also for being the clearest indication yet that a decades-old, once iron-clad alliance can no longer be taken for granted.

There have been crises in the US-Israeli relationship before, of course, such as when Barack Obama concluded a nuclear deal with Iran in 2015 that Netanyahu denounced as a "historic mistake".

But today's bitterness is new, especially coming from a president of the American Right, which has long held support for Israel to be a shibboleth.

It is particularly telling that the rancour comes at the end of a war the two countries entered into together and fought wingtip-to-wingtip. More importantly still, the most powerful of the two allies then concluded a separate peace with the enemy while failing to consult its supposed comrade in arms. And that deal struck by America and Iran – over Netanyahu's head – breaches a series of Israeli red lines all at once, leaving it perilously exposed.

Trump's feckless disregard of the single most essential obligation of an ally – that you do not forsake your friend – raises one pressing question: has the ultimate special relationship collapsed?

Existential crisis

On the surface, Trump's words earlier this week appeared to be driven by concern that Israel's offensive against Hezbollah, the Iran-backed terrorist group in Lebanon, could jeopardise his 14-point "memorandum of understanding" with Tehran.

"Too many people have been killed," he said. "You don't have to knock down an apartment house every time you're looking for somebody, because there are a lot of people in those apartment houses, and they're not all Hezbollah."

"They should have been able to do the job faster," Trump added. "It just goes on forever. And when that happens, it throws a negative light on the big deal, and that's the deal with Iran."

On Friday, a US official announced there would be an immediate ceasefire between Israel and Hezbollah, theoretically clearing the way for America to escape a costly war with Iran and save the global economy by reopening the Strait of Hormuz.

But, in reality, the president's outburst goes far deeper than an argument about the wisdom of military action in Lebanon. Rows between the two countries on that subject have often happened before.

What makes this different is not just Trump's actions, but how the current of American opinion is steadily becoming more critical of Israel, including among Republicans and even evangelical Christians. And all the while, the American Right is becoming increasingly sceptical of all foreign alliances, with no exemptions for any country – Israel included.

So the ceasefire in Lebanon – even if it should hold – will not paper over these cracks in what Washington diplomats have long believed to be America's only truly special relationship.

"If there's one thing that I truly worry about, that I really consider existential, it's the relationship with the US, because we need the US for everything," says Chuck Freilich, who served as Israel's deputy national security adviser under former prime minister Ariel Sharon.

"I thought the relationship was heading towards a crisis long before October 7, and then October 7 put it on hold for a bit, and then actually amplified it [because of the war in Gaza]. Then Trump came in, and that gave us another breather, but now this is happening."

Perhaps the most powerful termites gnawing away at the relationship are the opinions of millions of ordinary Americans.

The evidence shows that US popular support for Israel has plunged, with Democrats especially inclined to express fury over the war in Gaza, triggered by the Hamas atrocity on October 7, 2023, and Right-wing Republicans questioning how the alliance squares with putting America First.

A Pew survey conducted in March found that 60 per cent of Americans now have an unfavourable view of Israel, up from 37 per cent as recently as 2022.

Like so much else in America, sentiment is sharply divided along party lines: 80 per cent of Democrats hold a negative opinion of Israel, while a majority of Republican voters are still favourable.

But the same survey showed that for Republicans under the age of 50, Israel is almost as unpopular as it is among the general public, with 57 per cent holding a negative opinion.

Those numbers question the wisdom of the so-called "Netanyahu doctrine", which held that Israel's priority should be to focus on retaining the support of Republicans and evangelical Christians, reflecting the reality that American Jews comprise only 2 per cent of the population.

Avishay Ben Sasson-Gordis, an expert on US-Israel relations at the Institute for National Security Studies at Tel Aviv University, concludes that Netanyahu's gamble on how to manage US public opinion "didn't pay off". He adds: "Or at least, if it did pay off, it is now mostly done paying off."

'Catastrophic capitulation'

The Gaza war accelerated this trend. But the joint American-Israeli offensive against Iran, opposed by two-thirds of the US public, has widened the rift still further.

A campaign intended to overthrow the Islamic Republic, and remove the threat posed by its missiles, nuclear programme and sponsorship of terrorism once and for all, has instead left the regime in power – and probably stronger than before.

Having demonstrably failed to achieve their war aims, America and Israel have exchanged private recriminations. US officials have leaked the fact that Netanyahu met Trump shortly before the onset of the campaign, and by their account, promised that the regime would swiftly crumble.

Israeli officials, for their part, have blamed Trump for supposedly failing to arm and support an offensive by the Kurdish minority that might otherwise have threatened the leadership's grip on power.

As it became clear that the Islamic Republic was going to survive the onslaught – and once it had retaliated by closing the Strait of Hormuz – America's priorities shifted to averting a global economic meltdown and protecting its Gulf allies from a barrage of Iranian drones and missiles.

So Trump's main justification for striking a quick and partial deal to end the war was to ensure that Iran reopened the Strait, allowing oil prices to fall.

But for Israel, control of the waterway was always secondary to Iran's missile and nuclear capabilities. Hence Netanyahu said nothing about it when he reacted to the peace agreement.

"He didn't even mention Hormuz, and none of the reporters he took questions from asked about Hormuz," points out Sasson-Gordis. "[Even though] for most of the world, Hormuz was the war by this point."

While Netanyahu might be grimly familiar with America ignoring what he considers to be Israel's security interests – as he believes Obama did with the nuclear deal of 2015 – never before has a US president signed an agreement that breaches so many Israeli red lines all at once.

Trump's memorandum of understanding with Iran protects Hezbollah by demanding a halt to Israel's campaign in Lebanon, waives US sanctions on Iran's oil industry and lifts the blockade of its ports. The latter two steps, both immediate and unconditional, will place billions of dollars in the hands of Iran's leaders.

Even worse, there is nothing to prevent them from devoting that largesse to rebuilding their arsenal of ballistic missiles and rearming terrorists across the Middle East.

As the senior partner in the alliance, America's interests were always going to override Israel's in the event of a divergence. Yet the terms of Trump's agreement with Iran still hit the Israeli public and politicians like a bolt from the blue. In effect, the US president has allowed the Islamic Republic to secure its economic and financial future: he has handed its leaders their survival plan.

David Horovitz, the editor of The Times of Israel, denounced a "catastrophic capitulation" and called Trump "reality-challenged".

Others went still further. Nir Dvori, from Israel's Channel 12 News, said the deal was a "diplomatic October 7". Shimon Riklin, a Right-wing television host and ally of Netanyahu, called it "total surrender".

The prime minister, meanwhile, has pointedly said as little as possible about the deal, noting perhaps wryly that "additional challenges lie ahead".

Israel has received no understanding from its ally. On the contrary, US vice president JD Vance warned on Thursday that America was the only friend Israel had left, adding it could not kill its way out of problems.

"Anybody in Israel who thinks their biggest problem is the president of the United States needs to wake up and smell the reality of the situation that country is in," Vance said. "If I was in the cabinet of the Israeli government, I might not be attacking the only powerful ally that I have anywhere left in the entire world."

But the shock in Israel is all the more profound because, in his first term, Trump gave Netanyahu just about everything on his wish-list, from scrapping the Obama nuclear deal, to moving the US Embassy to Jerusalem, and brokering the Abraham peace accords with four Arab countries.

Yet the appearance of this fracture on Netanyahu's watch should not have been a complete surprise. In important ways, he may be its chief architect.

The administration antagoniser

Outwardly, Netanyahu is the most Americanised prime minister in Israeli history, having spent much of his early life in Philadelphia, where he attended high school, and Boston, where he studied at the Massachusetts Institute of Technology.

In 1976, after graduating, he stayed in America to work for Boston Consulting Group. He began his public career by serving as Israel's deputy ambassador in Washington and later its permanent representative at the UN in New York.

All this gave Netanyahu a mastery of American-accented English and, at least in his own estimation, a deep understanding of the superpower's domestic as well as foreign affairs.

Yet, from the very beginning, Netanyahu's affinity with the US went hand-in-glove with a remarkable ability to get under the skin of his American interlocutors. While he was often accused of tilting towards the Republicans, the truth is that his propensity to offend was strictly impartial: Netanyahu antagonised administrations of both political colours.

In 1990, as Israel's deputy foreign minister, he bluntly denounced the supposed "lies and distortions" behind Republican president George H W Bush's renewed effort to broker peace between Israel and the Palestinians. James Baker, then US secretary of state, retaliated by personally banning Netanyahu from entering the state department.

From that moment on, one American president after another identified Netanyahu as an intransigent obstacle to any resolution of the Arab-Israeli conflict.

Obama, who made the quest for peace with the Palestinians a priority for his first term, once resorted to threatening Netanyahu in the Oval Office. "You know, people often underestimate me," he told the Israeli leader in May 2009. "But I come from Chicago, where I had to deal with tough opponents."

Obama then drew a finger across his throat, gesturing exactly what he would do to his counterpart if there was any defiance. "The message was unmistakable," wrote Netanyahu in his memoirs. "It was meant to intimidate me. The fact that the American president delivered such an offensive message in our first official meeting was highly disturbing. The prime minister of Israel was being treated as a minor thug in the neighbourhood."

And yet through every one of these flashpoints, the military, intelligence and diplomatic cooperation forming the backbone of the alliance remained intact and even grew stronger.

Still, when Trump became president in 2017, Netanyahu was profoundly relieved and, in retrospect, that first term probably marked the pinnacle of US-Israeli relations. Trump even recognised Israeli sovereignty over the occupied Golan Heights, which every previous administration had withheld since the territory was seized from Syria in 1967.

Yet Trump soon wearied of Netanyahu's obduracy towards the Palestinians and his dismissive treatment of their leaders. "I saw what he was doing. He was embarrassing them," Trump said in an interview with the Israeli journalist Barak Ravid in 2021. "You know, you have to give people their dignity. And he was taking their dignity away. Bibi did not want to make a deal [with the Palestinians]."

When Joe Biden took office in 2021, the new president's relations with Netanyahu began warmly enough, reflecting the fact that the two leaders had known one another for decades.

The outbreak of the Gaza war, however, quickly soured their friendship. Barely two months after the October 7 attacks, Biden was already accusing Israel of "indiscriminate bombing".

When his efforts to broker peace in Gaza turned to dust, he blamed Netanyahu and privately described the Israeli as a "son of a b----", a "bad guy", a "bad f---ing guy" and a "f---ing liar", according to one account by the journalist Bob Woodward.

So Netanyahu has clashed with all four of the American presidents he has encountered as prime minister – and countless US diplomats and officials along the way.

"He certainly plays a unique role in this," says Freilich, "because some of [the American anger] is just antipathy towards him."

The great exception

But even if another politician were Israel's current prime minister, Trump would still have been under pressure from some in his Maga base to prioritise a swift end to the Iran war over Israel's security.

Before this conflict began, Curt Mills, the editor of The American Conservative asked: "Why are Israel's endless problems America's liabilities," adding: "Why should we accept America First – asterisk Israel?"

The conservative pundit Tucker Carlson, who championed Trump before falling out with him, told Israel's Channel 13 last month that the country had "lost its morality".

Carlson added: "I don't understand why the US has an obligation to pay for any of this, to send the weapons for it, lend its moral authority to Israel, to lend its diplomatic cover to Israel, to lend its air force and its navy and its military to Israel."

Freilich says that he has long feared precisely this shift in Right-wing American opinion. The image of a "heroic Israel of the early decades" has slowly been replaced in the eyes of many Americans by that of a domineering regional Goliath.

He laments decades of "pent-up American fury over the perception of Israel being the beneficiary of so much American aid and help in so many different areas – and not just military aid – and then taking a totally contrary position to American policy on the Palestinian issue".

Even before the Gaza war, he adds, Americans were beginning to ask: "How can you take billions and billions in aid, including under previous governments, and our strategic cooperation in 20 different areas, and the UN Security Council veto, and then you go and pursue the West Bank policy and settlements?"

For decades, Israel has defied America by expanding Jewish settlements in the occupied West Bank, using land that would be the core of any future Palestinian state, and making the conflict ever harder to resolve.

But this was never enough to shake the pillars of the America-Israel alliance, perhaps because those pillars are so strong and longstanding that they would be exceptionally difficult to topple.

That is particularly true of military and intelligence cooperation, and Israel brings plenty to the table: peerless intelligence coverage of the Middle East, probably the most advanced military in the world, and extraordinary technology.

Today, however, key elements of the alliance can no longer be taken for granted.

The current $38bn (£29bn) US military aid package – ironically, signed by Obama – expires in 2028. Netanyahu, recognising America's new willingness to question all of its alliances, said in January that he wanted Israel to do without all US military help and "taper off" the aid to zero over the next decade.

As for Trump, would he ever go to war alongside Israel again? And any future American president would surely think twice about taking military action against Iran, even if the regime were to use the oil revenues provided by Trump's deal to rebuild its missiles and nuclear programme.

Netanyahu himself may not survive the next Israeli election, which must come by October. Trump will leave office in January 2029, assuming he obeys the US Constitution.

But even after both leaders depart, they will leave behind a widening philosophical divide between their two countries.

Many Israelis – and not just Netanyahu – believe that America just does not understand that in the Middle East, only strength can keep you safe.

Meanwhile, many Americans – and not just Trump – want to see Israel setting as much store by diplomacy as it does by destroying apartment blocks in Beirut.

Today, regardless of the political futures of their current leaders, the two countries appear to be travelling different paths.

The most durable alliances rest not just upon a convergence of interest, but a shared view of the world. For decades, America and Israel saw themselves as facing the same enemies, defending the same values and countering the same threats.

Allies who fight wars together are supposed to be drawn closer by the searing experience of combat against a mutual enemy. America and Israel's joint war against Iran was, at first, presented as the very symbol of that. But historians may conclude that it became the great exception.

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