The Guardian view on the killing of a Hamas leader: the Middle East circles the abyss | Editorial

Dim hopes that a ceasefire in Gaza might be in view have been extinguished, for now at least, with the assassination of Ismail Haniyeh in Tehran. Israel has not claimed responsibility for killing the political leader of Hamas , but Iran’s supreme leader, Ayatollah Ali Khamenei, was swift to vow vengeance.

It came hours after Israel said it had killed Fuad Shukr , Hezbollah’s top military commander, in an airstrike in southern Beirut, blaming him for the attack that killed 12 children in the occupied Golan Heights last week. The militant group did not immediately confirm his death; ambiguity leaves it room for manoeuvre too. Add in recent strikes on the Yemeni port of Hodeidah , one day after Israel pledged revenge for a Houthi drone attack, and a pattern is clear.

But if Israel believes it is re-establishing deterrence, more deaths will surely result. They will come first in Gaza, though they are unlikely to be confined to there. Qatar, a mediator, was quick to point out that ceasefire talks are unlikely to prosper when the negotiator is dead. The international criminal court’s chief prosecutor recently issued a warrant against Haniyeh on war crimes charges. He was nonetheless seen as relatively more pragmatic than its military leader, Yahya Sinwar, and other hardliners in Hamas. A ceasefire and hostage release deal would not guarantee de-escalation, but it cannot happen without one.

Iran will not feel that it can ignore this attack, made shortly after Haniyeh attended the inauguration of its new president , Masoud Pezeshkian. Instead of projecting its strength with the grand gathering of its allies, Tehran has been humiliated by a glaring intelligence failure at a time of heightened security.

At other crisis points over the last 10 months – such as in April, when Iran launched its first ever direct military attack on Israel after the assassination of one of its commanders in Damascus – an all-out regional war has been avoided. The players have calculated their responses. That should not offer false reassurance; rather, each incident increases the risks . Each move may be calibrated, yet they are set at a higher notch than before. Look further afield and the US has just carried out a strike in Iraq in response to recent attacks on its bases by Iran-linked militias.

Meanwhile, Israel has had to deploy soldiers to guard detention centres because it cannot trust the police to fend off the far right, thanks to Mr Netanyahu’s extremist coalition partners. Knesset members and ministers were among the mob who broke into a base in protest after nine soldiers were arrested on suspicion of the torture and sexual abuse of a Palestinian detainee. That kind of internal breakdown, noted the analyst Dahlia Scheindlin, was welcome news for Israel’s enemies.

A year ago, with former political and military leaders from the US, Israel and European countries, a Tel Aviv thinktank held a war game that ended in a massive regional conflict. One organiser concluded: “There is no good mechanism for sending messages via military force; the messages arrived twisted.” But with the US preoccupied by its domestic issues, and Europe by Ukraine, diplomatic efforts are hobbled too. A regional conflagration is not inevitable. Those involved understand the disastrous consequences it would hold for them, whoever won. It can and must be averted. Yet each attack and counterattack creates a new path towards one and piles obstacles along the exit route.

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