To understand the escalation in Lebanon, we need to understand the minds of Israelis | John Jenkins

WWe cannot say that we could not have foreseen this latest escalation between Israel and Hezbollah. There has been a stalemate conflict between Israel, Hezbollah, Iran and the Shiite paramilitaries in Iraq since at least 2015. The immediate cause was Iran's efforts to expand its physical presence and that of its allies throughout Syria and Lebanon up to the Golan heights.

The Israeli Air Force has always tried to stop the Iranian supply of rockets and other ammunition from Iraq via Syria, particularly to Hezbollah. There were successes. But none of them could stop Hezbollah's strength as it acquired more sophisticated and precise missiles and gained extensive combat experience in Syria on the side of the Assad regime.

What has changed now are the Israeli calculations. A large majority of Jewish Israelis are pessimistic about the possibility of an agreement to end the conflict in Gaza. The belief that negotiations would bring lasting peace was shattered. It is almost certainly true that Prime Minister Benjamin Netanyahu has political reasons for prolonging the conflict. But while the majority of Israelis would likely want a different prime minister, many do not want to stop the war until they believe that both Hamas and especially Hezbollah – which has directly linked its actions to Gaza – have been neutralized as serious threats.

And that's because they see behind both groups an Iran dedicated to their destruction. They believe that the fine words of Iran's new Prime Minister Masoud Pezeshkian and his Foreign Minister Abbas Araghchi in New York this week are just another example of Iranian duplicity. They know that Israel alone cannot stop Iran's war of attrition against them. But if they can at least disable Hezbollah and remove Hamas as a military power in Gaza, then they will have reduced the threat to a manageable level.

I vividly remember the frantic activity at the United Nations in New York over Christmas and New Year 2008-2009 as Western allies attempted to bring about a ceasefire to end Operation Cast Lead in Gaza. The Israelis were deeply unhappy about the adoption of a ceasefire resolution in the Security Council and, in their opinion, did not have time to complete the task. But what they considered “getting the job done” in 2009 was a matter of limited punitive measures as a deterrent. Despite the horrific human cost of this conflict and the massive damage to Israel's reputation internationally and regionally, most Israelis think that this time these conflicts are truly existential.

The missing piece in all this, of course, is, as David Petraeus used to ask Iraq, “How does this end?” Disparaging Hezbollah as a fighting force is one thing. It is essentially what the Israel Defense Forces attempted in 1982 under various circumstances. Israel can win this Slaughter. But in the end it cannot win the war if there is no political way out.

There are two key elements to this. One of them is eliminating or neutralizing the real existential threat posed by Iran. In practice, that means long term Neutralize from Hezbollah. The second is Palestinian self-determination – which is necessary for the more important things in the region (in particular economic diversification, development and integration, combating extremism and tackling the climate crisis) are seen as achievable.

Iran doesn't want a hot war. It believes it is winning the war of attrition. So why take the risk? Hezbollah doesn't want anything like that either – especially if Israel avoids the mistake of deploying ground troops. Israel would probably prefer to avoid it too. It has been preparing for war with Hezbollah for years and has a number of options it can use before an invasion. But all this will not necessarily prevent a general war.

Iran and Hezbollah, in particular, must calculate how much damage they can endure without losing their critical capabilities and reputation. Israel must be confident that it can return 80,000 Israeli citizens to the north without fear of harm being done to them. And the problem with escalation ladders is that they are usually missing several rungs: this time it would only be enough if a ballistic missile hits an ammonia factory in Haifa, for example, or someone tries to assassinate a high-ranking minister. It is not clear to me that the UK (or perhaps anyone) can significantly influence these calculations.

Nice words at the UN are no longer enough. And as we saw with the recent arms deal and announcement of new naval deployments, the Biden administration simply will not abandon Israel while it is at war. But what we can do is think urgently about where we want to be together in five years and work out in much greater detail than before how we will get there.

This is not just about the USA and its Western allies. This time the Gulf states – and especially Saudi Arabia – will be the central players. The price of normalization with Israel has not gone away. But the price has increased. This will certainly include the effective containment of Iran and its allies – and a response to real, not just declarative, Palestinian statehood. And this time we have to do it. Otherwise the pain we see now won't just not go away. It's going to get a lot worse.

• Sir John Jenkins is an Associate Fellow in the Middle East and North Africa Program at Chatham House. He was ambassador to Syria from 2006 to 2007; Director of the Foreign Office for the Middle East and North Africa 2007–2009; and Ambassador to Iraq 2009-11

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