With the death of Hamas political leader Ismail Haniyeh in Tehran, Israel appears to have eliminated top officials in two organizations committed to its destruction within the space of a day.

On Tuesday, in what appears to have been a drone strike, Israel said it killed Hezbollah’s deputy military commander, Fuad Shukr. In one sense, this is nothing new. Israel has killed dozens of Hamas and Hezbollah officials and militants over the years.

The executions, invariably conducted in the name of deterrence, changed little, even if they demonstrated brutally impressive Israeli capabilities. The attacks came in response to the deaths — attributed by Israel to Hezbollah rockets — of 12 Arab teenagers from the minority Druze religious sect in the occupied Golan Heights.

So at a time when innocent civilians are being killed daily — by their thousands when it comes to Palestinians in Gaza — it’s also disingenuous to pretend any moral outrage over the loss of two men whose hands had been steeped in blood for decades.

Even so, there are reasons to fear this pair of assassinations could soon light the fuse to a potentially catastrophic regional war that would be in the interests of neither Israel, Lebanon nor Iran. The first of these is the locations of the strikes, in Beirut and Tehran, a decision inevitably seen in both capitals as a serious Israeli escalation. Hezbollah and Iran have pledged retaliation.

The second reason to fear a wider war is the choice of Haniyeh as a target. This, again, came as no surprise; Israel already had killed much of his family. But Haniyeh was the political face of Hamas, living in exile in Qatar, and the man responsible for handling negotiations over a cease-fire in Gaza. While Hamas is an opaque organization, he was widely viewed as the more pragmatic of its leaders, particularly when compared with the group’s fanatical commander in Gaza, Yahya Sinwar.

It's hard to see how killing Haniyeh can facilitate those talks, or to overestimate how critical their outcome will be to the region’s future. Hezbollah has long made clear that it will stop firing on northern Israel only once a cease-fire in Gaza has been reached. That matters, because Israeli officials have made equally clear that if the shooting doesn’t end in time to return evacuees and open schools on Sept. 1, they will do what it takes — including a ground invasion of southern Lebanon — to build the buffer zone required to make them secure.

At the same time, a truce in Gaza is a prerequisite for the potentially far-reaching peace deal envisioned by Washington, which would include a security pact with Saudi Arabia. This agreement would include a political resolution for Gaza, stabilize Israel’s position in the region and isolate Iran. In other words, the stakes could hardly be higher. Negotiators thought they were close, yet an agreement remains elusive. Each side has, plausibly, accused the other of adding new demands to scuttle the talks.

Ever since the savage attack Hamas launched against Israel on Oct. 7, Sinwar has made no secret that his goal is to widen the conflict, first of all by drawing in Hezbollah. By obstructing peace in Gaza, he makes that more likely and delays the personal reckoning he may face from ordinary Palestinians in Gaza when the shooting stops.

His decisions have brought them devastation, as was his intent. Within Israel, the extreme and, frankly, unhinged nature of Prime Minister Benjamin Netanyahu’s coalition government has never been clearer.

In recent days, far-right Israelis — including at least one Knesset legislator — stormed a military detention center to protest the arrest of army reservists, found by an internal investigation to have tortured and sodomized Palestinians detainees.

These, too, are fanatics. Some have said openly that there should be no limits to the mistreatment of Palestinian prisoners, or to the Jewish annexation and settlement of occupied Palestinian territories. They’re also adamant that there should be no Gaza cease-fire. There is a symmetry here that no appeals to Israel’s special status as a civilized democracy at war with “barbarism” — such as Netanyahu made in a July 24 address to a joint session of the U.S. Congress — can conceal.

Because only by appeasing the extremists in his cabinet can Netanyahu remain in power. And only while in office can he delay the reckoning he too will face when the war ends, in the form of criminal corruption charges and an investigation into the failures that permitted Hamas’ Oct. 7 attack to succeed.

This is a tragedy. The deep flaws of individuals are threatening to turn an opportunity, no matter how complex and fragile, into unmitigated disaster for both Palestinians and Israelis. Israel must know, after Hamas’ survival through almost 10 months of total war in Gaza and multiple fruitless past attempts to wipe out Hezbollah in Lebanon, that it can’t achieve security by force alone.

Yet by throwing up new demands for a Gaza cease-fire (such as retaining control of the so-called Philadelphia corridor along the border with Egypt), and killing the Hamas leader who was overseeing cease-fire negotiations, Netanyahu appears bent on cutting off all other paths.

As Boaz Ganor, the counterterrorism expert and president of Israel’s Reichman University, said recently, “Hamas is a tactical threat, Hezbollah is a strategic threat, and Iran is an existential threat.” By treating Hamas — a relatively weak and geographically isolated force — as more than it is, he warned, the country has been playing right into the hands of its enemies. He’s right.

If Netanyahu now opens a second front against Hezbollah in Lebanon, then regardless of the provocation he will be responsible not just for the failures of Oct. 7, but for turning a manageable tactical threat into one that risks the future of Israel’s thriving economy, its democracy and potentially the state itself.

No wonder 64% of Israelis said in a recent poll for Israel’s Channel 12 by the Midgam research firm that they favor a Gaza cease-fire. No wonder 72% said their prime minister should resign.

Marc Champion is a Bloomberg Opinion columnist covering Europe, Russia and the Middle East. He was previously Istanbul bureau chief for the Wall Street Journal.