The advance word was that this was to be a "holding meeting" and not much more. Barack Obama and Binyamin Netanyahu would not launch some grand initiative for the Middle East. Instead they would sit together, chat chummily and pose for photographers – particularly important given what happened a couple of months back, when an angry Obama kept Bibi waiting for hours in the West Wing, only to cut their meeting short without so much as posing for a souvenir snap.

Accordingly, today's summit was all warm hugs and making nice. Obama spoke of the "special bond" between the two nations – even if there did have to be the occasional "robust discussion". Bibi nodded, adding that disagreements were what you got in a close "family" relationship like this one. Reports of any strain between them were "flat wrong", and to prove it Bibi invited the Obamas to Israel; Michelle showed Sara round the White House; and reporters were kept waiting during a long Bibi-Obama lunch, surely proof that the two men just couldn't get enough of each other.

For all that, the advance billing of a holding meeting was not so far off the mark. The US president was certainly in no rush to make waves: he is four months away from midterm elections, in which support for Israel threatens to become an issue, at least in the handful of states where Jewish voters might make a difference. In several congressional contests Republicans are making mischief over the administration's recent relative firmness towards Israel, with one candidate accusing Obama of "browbeating" the Jewish state, while others suggest the Democratic administration is fraying the historic ties that have bound the two countries. Small wonder, then, that Obama was and remains keen to be all smiles with Bibi – at least until polling day on 2 November.

The Israeli PM does not face imminent elections, but he too has been happy to go along with a strategy of pause and delay. For Netanyahu inaction is always preferable to action: only a demand for tricky concessions – say an extension of the current, partial moratorium on settlement building in the West Bank – might imperil his fragile coalition, by prompting the ultra-hawkish parties to bolt. So long as the Americans are not asking anything of him, Bibi can stay comfortably in his seat.

There is a larger explanation for why the prime minister might be fond of stasis and inertia. The operating assumption held by both him and the nationalist right he leads is that Israel has time on its side. This is a belief deeply ingrained, one that draws sustenance from a century of Zionist history. The first Jewish settlers in Palestine pushed the boundaries of the possible, establishing themselves in places that initially seemed insanely ambitious, only for time to reward their daring. The Jews accepted a UN partition plan in 1947 that gave them 56% of Palestine, only to see their share leap to 78% by the end of the war of 1948-9. Playing the long game has worked before and, the Israeli right assumes, it will work again.

You can see why Bibi would be drawn to such thinking. Each day that passes entrenches the Israeli presence in the West Bank. Consider that there were no Jewish settlers in 1967, around 120,000 in 1994 and more than 300,000 now – those numbers alone, which exclude East Jerusalem, constitute a powerful argument for playing it long, letting time change the facts on the ground until they are unalterable.

Besides, what's the urgency? The Israeli economy is ticking along nicely, defying the global trends; the beachside cafes are full; Tel Aviv is even becoming the hot destination for gay tourism. Why risk change when the status quo is so tolerable?

And yet the underlying assumption is almost certainly wrong. Israel does not have time on its side. On the contrary, time is running out fast.

Israel is surrounded by evidence that it is, in the words of one Ha'aretz columnist, "hurtling down the slippery slope of pariahdom". The Gaza flotilla episode exposed that fact most starkly, as Israel found itself isolated diplomatically, chastised by those it normally relies on as friends.

First among those has always been the US. Israel has long been able to depend on rock-solid support from a Washington that saw merit in a loyal, semi-dependent state in a region that was unreliable at best and hostile at worst. But now that calculus has been shaken. Note the 54 Congressmen who issued a statement rebuking Israel over the flotilla. Note the paper by Anthony Cordesman, a fixture of the US foreign policy establishment, asking if Israel has become a "strategic liability" for America. Note too the comments of David Petraeus, now Nato commander in Afghanistan, warning that Israeli intransigence was adversely affecting US interests in the Middle East. This adds up to a new climate of opinion in which Obama can afford to be firm with Netanyahu because he knows he is not alone.

The second source of previously iron support has been the mainstream Jewish diaspora, especially in the US. For decades, the official voices of American Jewry have uttered only words of unity and support; criticism was confined to the fringes. But now that too is changing.

The institutional manifestation has been J Street, which in three short years has signed up some 100,000 supporters for its alternative to the dogmatic Israel-right-or-wrong stance of American Israel Public Affairs Committee. A key recent text is an essay by Peter Beinart that appeared in the New York Review of Books, castigating the US Jewish leadership for failing to condemn the ever-rightward drift of Israeli policy.

Of course there is nothing new about Jewish opponents of Israel: they are older than the country itself. But what makes these interventions different is that they come from those who are avowedly Israel's friends. J Street's slogan is that it is "pro-Israel, pro-peace"; Beinart is a former editor of the staunchly Zionist New Republic.

There are echoes outside the United States, too. In Europe, JCall, an online petition, has rapidly attracted the signatures of those who have previously devoted themselves to public defences of Israel, including the French glamour-intellectuals Bernard-Henri Lévy and Alain Finkielkraut. Even the head of Britain's biggest pro-Israel charity last month insisted on the right of diaspora Jews to speak out, and bemoaned the lack of a peace strategy from the Israeli government.

It is this that should shatter any Israeli complacency. For these are stirrings from deep within the pro-Zionist mainstream. They cannot be dismissed as the words of implacable enemies of Israel or the Jews; they are palpably nothing of the sort. Nor can they be ignored. Beinart's essay began with survey evidence showing young American-Jewish youth alienated and remote from Israel, with many expressing "a near-total absence of positive feelings". That sentence should strike fear into all those looking to Israel's long-term future.

Until now, the chief long-range concern of the Israeli right was demographic, the fear that eventually Israel would rule over more Arabs than Jews, given the combined populations of Israel, the West Bank and Gaza. Now they have another concern: "delegitimisation", what they perceive as a global campaign to ostracise, or boycott, Israel, until it is banished from the family of nations. It is undeniable that Israel has bitter enemies. But the longer the occupation endures, the more Israel risks losing its friends. Netanyahu has to realise that Israel does not have time on its side: it needs to end this conflict – and with the utmost urgency.