Israelis enjoyed a lavish party last week to mark the nation’s seven eventful decades, but the threat to its existence could hardly have been greater

There were fireworks, concerts, torch processions and parties throughout the country. In Jerusalem the night sky was illuminated by 300 drones that coalesced to form images of favourite Israeli symbols, such as the national flag and a dove with an olive branch in its mouth. The celebrations included a live, televised retelling of Jewish history dating to biblical times. In one scene children with yellow stars pinned to their clothes fled marching Nazi soldiers. Another showed pioneers building the fledgling Jewish state.

Benjamin Netanyahu, Israel’s prime minister, helped lead the national extravaganza, despite objections that his presence contradicted the event’s traditional, non-political character. This moment – the 70th anniversary last Wednesday of Israel’s independence, according to the Hebrew calendar – marked the country’s emergence as a rising world power, he declared.

Israel offered the hand of friendship to all, Netanyahu said. But there should be no doubt, Israel was here to stay: “In another 70 years you’ll find here a country that is 70 times stronger, because what we’ve done until today is just the beginning!” Israel’s ability to protect itself was “the essence” of independence, he said.

If Netanyahu sounded defensive, he had reason. Israel has faced many crises since its birth in 1948, including wars in 1967 and 1973, conflicts in Lebanon, and endless confrontation with the Palestinians, for whom Israel’s independence is known as the Nakba (“the catastrophe” or “cataclysm”). It was the day 700,000 people lost what they considered their homeland. Palestinians were not partying last week.

Yet according to Israeli and regional experts, the storm now gathering around Israel’s borders potentially surpasses in severity anything the country has faced throughout its short and difficult history. Whichever way you look, in any direction, trouble looms. At its heart, connecting all the geopolitical Scrabble pieces, is one four-letter word: Iran.

In Syria beyond the Golan Heights, in Lebanon to the north, in Gaza to the south, in Iraq, and possibly even in Jordan to the east, Israeli leaders are watching with growing alarm as Iran’s physical and ideological presence and influence steadily spread.

Iran’s theocratic Shia Muslim regime has sworn to destroy the state of Israel – an oft-stated aim Israelis say cannot be dismissed as mere rhetoric. And Iran is edging closer day by day. The growing military strength of Iran’s Islamic Revolutionary Guard Corps (IRGC) and its Quds Force and associated Shia militias in Syria, where with Russia they have played a key role in bolstering Bashar al-Assad’s regime, is the focus of Israeli concern.

“They’ve succeeded in the war for Assad to survive. Now their first priority has changed and Israel is the target,” retired Major General Yaakov Amidror, Netanyahu’s national security adviser from 2011 to 2013, told the Wall Street Journal. “For us it is essential to stop Iran and for that we are ready to take the risk of a war.”

Allowing Tehran to solidify its military presence in Syria would be akin to “agreeing to the Iranians placing a noose around our necks,” Avigdor Lieberman, Israel’s hawkish defence minister, has warned.

“We will not allow Iranian consolidation in Syria. We won’t allow any restriction when it comes to Israel’s security interests … We are facing a new reality – the Lebanese army, in cooperation with Hezbollah [Lebanon’s powerful pro-Iran militia], the Syrian army, the Shia militias in Syria, and above them Iran – are all becoming a single front against the state of Israel,” Lieberman said.

Expressing what appears to be the consensus view, Mark Sofer, Israel’s ambassador to Australia, was blunt: “Iran cannot stay in Syria, period. We’re not going to have them on the border … Our position is clear, they have to get out and go home.”

Writing in Foreign Policy magazine, Dov Zakheim, the former US undersecretary of defence, said the Israelis feared both Iranian consolidation and Russian interference in their operations. “Coupled with Hezbollah’s growing strength, and the weekly Hamas-inspired protests in Gaza, Israel faces the spectre of a three-front war for the first time since 1967.” Zakheim also warned of a possible future Iranian-inspired insurrection in Jordan, similar to what he said Tehran had been attempting in Bahrain.

Iran’s intentions remain opaque. Politicians, officials and state media regularly threaten Israel’s annihilation. And it is indisputable that Tehran has extended its regional reach in Lebanon, Syria, Iraq, Afghanistan and Yemen, where Tehran backs rebel forces opposed to Saudi Arabia. But it insists its stance is defensive.

In a speech in February, celebrating the 1979 revolution that toppled the shah, Hassan Rouhani, Iran’s cautious president, called for unity in the face of what he called “Israeli plots”. Hundreds of thousands of supporters in Tehran’s Azadi Square chanted the traditional slogans, “Death to the United States” and “Death to Israel”.

But, like Israel, Iran is politically divided. How much of this is ritual and how much settled policy is unclear. What does seem plain is that Rouhani and the IRGC commander, Major General Qassem Suleimani, have competing agendas.

Again, not unlike Israel, Iran feels surrounded. Maps of the Middle East show a country ringed by US military bases from Turkey to Bahrain to Afghanistan. Then again, Iran’s principal opponent is arguably not Israel at all but the US-aligned Saudi Arabia, the self-appointed leader of the Sunni Muslim Arab world.

In backing Assad, some analysts believe, Iran’s aim is to ensure Syria does not slip into the pro-western “enemy” column, rather than to recreate the Persian empire or push Israel into the sea – or so the argument goes.

Latest events on the ground undermine this. In recent weeks Israel and Iran have engaged in direct military exchanges for the first time. It started in February, when the Israelis shot down what they said was an armed Iranian drone entering their territory from Syria. Since then, there have been at least two Israeli air raids on the T-4 airbase in central Syria, home to IRGC troops, ground-to-air missile batteries and drones. The second raid, now officially acknowledged by Israel, killed several Iranians. Tehran has vowed to exact revenge.

In anticipation of a retaliatory Iranian strike, Israel cancelled its participation in air force exercises with the US last week and took the unusual step of publishing intelligence satellite photos of five Iranian installations in Syria.

Quoting military officials, Thomas Friedman, the New York Times analyst, reported that Israel “may use the opportunity [afforded by any further Iranian provocation] to mount a massive counter-strike on Iran’s entire military infrastructure in Syria”. Targets could include airbases and Iranian-run factories making GPS-guided missiles capable of hitting Israel, which Iran planned to supply to Hezbollah, officials told Friedman.

In short, the message from Tel Aviv to Tehran was clear: if you come for us, we are ready, and we can hit you hard. Yet by raising the possibility of a big escalation, Israel ran the risk of provoking an even more aggressive response.

That was probably deliberate. Last week’s “locked and loaded” Israeli stance was also intended for consumption by the world at large. The obvious implication was that any clash with Iran could quickly suck in existing Syria-based US and Russian forces on opposing sides.

Yet such scenarios are not straightforward. When Israel’s back was against the wall in the 1973 Yom Kippur war, it turned to the US for help. Netanyahu would doubtless like to do so again, if necessary. Yet despite vows of eternal friendship and, for example, his ostensibly supportive decision to relocate the US embassy in Jerusalem, Donald Trump has proved an unreliable, unpredictable ally.

Since Trump took office last year the US has eschewed serious efforts to revive the Israel-Palestine peace process. One consequence is renewed trouble on the border with Gaza, which flared again last month.

Trump’s threat to tear up the west’s nuclear deal with Iran next month, while supported by Netanyahu, has added to the sense of a region spinning into chaos. So, too, did last weekend’s risky and, according to Israeli officials, ineffective cruise missile strikes on Syria by the US, Britain and France.

Meanwhile, Trump’s White House continues to insist that, far from pushing back Iran in Syria, the intention is to withdraw American forces as soon as possible, even if the fight against Islamic State – the reason for its presence in Syria – remains unfinished.

As often in the past, Israel could again find itself isolated and alone – with perhaps only the Kurds in its corner. “The consequences [of Trump’s statements] are clear,” said Amidror. “Israel may find itself having to do the critical job of containing Iran in the Levant by itself.”

The linked possibility that Russia, Assad’s most powerful ally, could also be dragged into a wider, military conflict is both paradoxical and alarming. Paradoxical because, by all accounts, Vladimir Putin, Russia’s president, believes he has rescued Assad. He would reportedly prefer to cut his losses (and costs) in Syria and, like Trump, bring his forces home.

Putin does not want to be drawn into a bigger fight, and certainly not for Iran’s sake. Russia has coordinated with Israel to avoid military clashes until now. But those arrangements are reportedly falling apart under the pressure of events.

Russia’s involvement, deliberate or otherwise, in any great confrontation on Syrian soil would inevitably become entangled in Moscow’s other disputes with the US over chemical weapons, the Salisbury poisoning, Ukraine, cyber-attacks and election meddling. The overall mix could prove explosive.

Right now, most agree, Israel and Iran are grappling on a cliff edge. A step too far could prove disastrous for one or both. Yet the struggle is about far more than the enmity of these two inveterate foes. A wide range of intractable, neglected and combustible international issues are coming together, all at once, all in one place. The result, 70 years on, could be a new Nakba of truly dreadful proportions.

“The finger is on the trigger and the missiles are ready. You [Israel] are living in the dragon’s mouth.”

Hossein Salami, deputy commander, Iran’s Islamic Revolutionary Guards Corps

“Iran has the ability to obliterate Israel and, when prompted, to turn Tel Aviv and Haifa into dust.”

Ali Shirazi, Iranian cleric

“It’s seriously not worth it to test the state of Israel.”

Avigdor Lieberman, Israel’s defence minister

“We will fight whoever tries to harm us. We will exact a heavy price. The people will stand strong.”

Benjamin Netanyahu, Israeli PM