BOTTOM LINE UP FRONT — Israel announced Thursday that it had killed its most wanted man, the Hamas leader Yahya Sinwar, an act that several Cipher Brief experts called one of the most significant events in the year-long Gaza war - with ripple effects that will be felt across the Middle East.
It's a seismic event in a region that has seen more than its share lately. There are immediate questions of leadership for a battered and badly degraded Hamas, as well as a fundamental choice for Israel: whether to use this moment to pursue a ceasefire deal to return the remaining hostages in Gaza, or to press its advantage against a badly weakened Hamas.
In the 24 hours that followed the news of Sinwar's death, The Cipher Brief turned to a half dozen experts from the intelligence and diplomatic spheres - all with deep experience in the region - and asked for their immediate reactions and thoughts about the way forward. They touched on SInwar's potential successors, that choice facing Israel, the implications for Iran, and how the moment may be viewed from Washington.
THE CONTEXT
- Yahya Sinwar was born in 1962 in Gaza and joined Hamas in the late 1980s. He founded and led the group’s security and intelligence branch known as Majd.
- Sinwar was imprisoned in Israel in 1988 and given four life sentences for the abduction and murder of two Israeli soldiers and the killing of suspected Palestinian collaborators. He was released in 2011 along with nearly 1,000 other prisoners in exchange for Gilad Shalit, an Israeli soldier who had been captured by Hamas.
- After his release, Sinwar coordinated Hamas’s political leadership and military wing. He was elected head of Hamas’s political bureau in Gaza in 2017.
- Sinwar is widely believed to have been the mastermind of the October 7, 2023 raids and massacre in Southern Israel. After Israel's war against Hamas began that month, Sinwar was also seen as the group's key decision maker in negotiations over the return of hostages held in Gaza.
- On October 17, 2024, Israeli military officials said Sinwar had been killed in a surprise encounter between Israeli troops and Hamas fighters in the southern Gaza Strip. He reportedly “engaged in combat” with Israeli soldiers and then ran into a building which was subsequently hit by Israeli fire. The Israeli forces realized only later that he was among those killed in the battle.
- Israeli Foreign Minister Israel Katzannounced Sinwar’s death, calling it “a great military and moral achievement for Israel," and added that it “creates a possibility” to rescue hostages in Gaza and rid the enclave of Hamas and Iranian influence.
- Israeli Prime Minister Benjamin Netanyahusaid that while Sinwar’s death improved the chance for peace and marked “the beginning of the end” of the Gaza war, the conflict would continue because “our task has still not been completed.”
- Khalil al Hayya, a top Hamas figure in Gaza, confirmed Sinwar’s death on Friday, saying that the “martyrdom” of Sinwar and others “will only increase the strength and resilience of our movement.” He added that the hostages in Gaza will not be freed until Israel ithdraws from the enclave.
- Sinwar is the latest among senior leaders of Hamas to have been killed by Israel, following the assassinations of political leader Ismail Haniyeh in Tehran and military wing head Mohammed Deif in an airstrike.
THE EXPERTS
First reactions
Grappo: This is probably one of the most significant days in this war. [Sinwar] was the key figure, and this is unquestionably a major blow to Hamas. It's not going to kill Hamas, but it's going to be a devastating blow, more on the morale than the military side. They've already lost the command and control that they had just six months ago. And with the loss of Sinwar, we could see disputes among mid-level commanders who are left to decide who's going to lead the fight.
Doyle: The deaths of Hamas leader Sinwar and Hezbollah leader [Hassan] Nasrallah are, for Israel, equivalent to what the deaths of [Osama] bin Laden and [Ayman] al-Zawahiri were for the United States. These men were accountable for the killing, injuring, kidnapping, and terrorizing of countless Israelis, Americans, and other allies. They were single-minded in their determination to destroy Israel and pressure the U.S. to abandon our Middle Eastern interests and allies. Their reign of terror did not prevail.
Roule: The architect of the October 2003 massacre and Hamas’ murderous reign of terror is dead. As with the deaths of Bin Laden or Nasrallah and their senior lieutenants, the ideological DNA of Hamas has now been changed. And Sinwar’s death removes an adamant and bloodthirsty opponent of compromise on the ceasefire talks.
Ross: Yahya Sinwar had one mission: the destruction of Israel. It did not matter what the cost was to Palestinians; for him, they were expendable as part of the struggle. [Sinwar] treated the Palestinian people as willing martyrs for this struggle, although he never asked them if they wanted to be martyrs.
Hamas after Sinwar: "never been worse"
Doyle: The deaths of Sinwar and Nasrallah will not mark the end of Hamas or Hezbollah, any more than the deaths of bin Laden and Al-Zawahiri marked the end of al-Qaeda or the oxygen it feeds to its affiliates, the Taliban and ISIS-Khorasan.
Grappo: Who's going to assume the leadership of Hamas? That's a difficult question, because the Israelis have taken out quite a few of them. I wonder now about the wisdom of having taken out [political leader] Ismail Haniyeh, because if we can say such a thing, Haniyeh was considered a more moderate and accommodating figure within Hamas, and were he still alive, he might be willing to look at some kind of a ceasefire, perhaps something beyond that. But he's no longer around, not in play.
The most likely successor in my view is Khalil al-Hayya. He is generally considered to be the deputy leader of Hamas in Gaza. And he's another hardliner.
Roule: Sinwar’s death opens both Hamas’ political and military wings to new leadership. The Hamas Shura Council – or at least those outside of Gaza – will likely meet to discuss the group’s next leader.
Political wing successors could include Hamas founders Mousa Abu Marzouk and Khaled Meshaal, or perhaps Khalil al-Hayya, the political bureau deputy. All of these actors have experience engaging foreign interlocutors, making them at least known commodities to Western diplomats seeking to revive hostage talks. But none have Sinwar’s iconic stature and ability to influence the Gaza and West Bank populations.
Replacing Sinwar as Hamas’ military leader will be more difficult, but this may not matter; at his death, Sinwar’s ability to direct operations was modest. The survival of the Hamas military wing in Gaza will require an experienced militant with name recognition. Mohammed Sinwar [Yahya Sinwar’s brother] might be a possibility. If he becomes the accepted head of Hamas, a compromise that produces a ceasefire and release of hostages will be extremely unlikely. Mohammed shares his brother’s deep hatred for Israel and commitment to violence.
Goff: Mohammad Sinwar is said to be a meaner version of his deceased brother. He made his name by being the internal enforcer, responsible for the murder of fellow Palestinians who were suspected of treason.
Succession may be less important than what they do right now with those remaining hostages. The hostages are the last remaining currency that Hamas has – with their leader dead and with succession unclear, the hostages are the only thing they have left to bargain with. This is an existential threat to Hamas. It's never been worse for them.
Grappo: The Israelis have done a very effective job in eliminating Hamas' bench. But there are still a significant number of fighters left within Hamas. We're talking on the low end, 7,000; on the high end, 10 or 11,000. By some assessments, Hamas is enjoying its best recruitment ever as a result of the war, which has driven a lot of young Gazans to join them who might have not done so 13 months ago.
Israel ’s next move – and the chances for peace
Grappo: The real question is, what is Israel going to do at this moment? They may decide to press the case militarily, which they most certainly can.
On the other hand, [Israeli Prime Minister Benjamin] Netanyahu could choose this moment to present a proposal to Hamas to release the hostages, lay down their arms and say, We'll declare the war over and they go from there. That kind of proposal, with the help of the international community, could potentially work. It's all a question of how serious the remaining Hamas fighters would be with respect to laying down their arms and giving up the fight. My personal view, and it's probably the view of the majority of the Israeli leadership, is that many of them would not do so.
Ross: Now is the moment for Prime Minister Netanyahu to declare that Israel’s successes make possible an end to the war, provided the hostages are released. He can reframe the issue and put the onus on Hamas to end the suffering of Palestinians in Gaza. Yes, Israel can weaken Hamas further in Gaza, and Hezbollah further in Lebanon, but it also has to have a clear criteria of victory and know when to stop—and act in a way that makes political outcomes, not insurgencies, possible. These considerations should also inform how the Israelis choose to respond to the Iranian October 1 ballistic missile attack. Iran must see there is a cost for that attack, and Israel’s retaliation should be guided by how it can best demonstrate to Iran that Israel could do much more, and how vulnerable Iran is, should it decide to respond and continue strikes.
Corn:The Israelis will continue to pursue targets. There will be someone that will replace Sinwar, and the Israelis will continue to go after them as they've done to Hezbollah from the other side. There's a lot of hope maybe in the West that this is an opportunity for a ceasefire. I'm skeptical. Netanyahu has made it clear that he sees that he has an opportunity to undermine the Iranian regime and to continue to humiliate them. I think that they feel that they have an advantage now and they're going to press that advantage.
Goff: In terms of the war right now, the only people talking about a ceasefire are in the West. So I think that the chances of any kind of immediate ceasefire are zero, and that the Israelis will use this time to continue to press their current advantage over these forces.
What this means for Hezbollah
Roule: Sinwar’s death is another defeat for Hezbollah. The Lebanese group finds itself locked into the seemingly endless devastation that comes with joining Hamas in a losing war against Israel. If the new Hamas leadership accepts a ceasefire or acknowledges its defeat, Hezbollah will likely seek a ceasefire with Israel, if only to survive and protect its position in Lebanese politics. If Sinwar’s successor continues to fight, Hezbollah will likely feel compelled to do so, at least in the near term.
Ross: Like Nasrallah, Sinwar miscalculated, and the demise of both of them means that the Iranian so-called Axis of Resistance is dramatically weaker than it was. Israel now has remarkable military and intelligence achievements, but to be enduring they must be translated into political outcomes.
Doyle: In the coming days, Hamas and Hezbollah will regroup, pick new leaders, consult with Tehran, and announce whether they remain committed to terrorizing and war or wish to negotiate for a ceasefire. On this point, Tehran must choose and act wisely. They must consider that the innocent people of Lebanon are tired of war; tired of poverty; tired of the outcome of Iranian interventions. The innocent people of Gaza are exhausted. They are starving, and dying. Tehran and its Axis Armies have much blood on their hands, and nothing to show for it.
What it means for Iran
Roule: Israel’s security establishment has now destroyed Hamas and Hezbollah as strategic threats and killed a generation of their most important and experienced leaders. Iran’s power projection in the region has been severely reduced.
Tehran likely saw [Sinwar’s death] as inevitable. Nonetheless, one can imagine the fury and despair that Iran’s leadership and Revolutionary Guards must feel as they watch Israel eradicate their closest partners and dismantle decades of investment.
Tehran will likely play the long game. The Quds Force has not gone away. Until it does so, Iran’s malign regional adventurism will remain a constant. Its hold in Iraq, Syria, and Yemen remains. Tehran probably expects that Hamas and Hezbollah will survive to be rebuilt, in part because neither the Lebanese nor Palestinian political systems are capable of replacing them in their respective societies.
Corn: The Iranians are in a very tough situation because I don't think there's much they can do without starting a bigger war – which I don't think they want.
The Iranians made a strategic miscalculation. They've had their number one piece on the chessboard in the axis of resistance decimated – Hezbollah, which was their pride, considered the most effective militia that they had. Hamas has now also had its leadership decimated. Rebuilding is probably not even on the agenda right now. They've got to survive.
Goff: For Iran, this is a case of, be careful what you wish for. The Iranians were not aware that Hamas was launching that attack last year, on the 7th of October. The leaders in Tehran were just as surprised as anybody else. They kind of lost control of their proxies. And now the Israelis, in just the last few weeks, have dramatically turned the tables on the Iranians.
The Iranians went from feeling smug and having their proxies encircling Israel to now being on their back foot. They're waiting for a retaliatory strike by the Israelis. And their proxies – the Houthis, Hezbollah and Hamas – are all under great pressure.
The U.S. response
Roule:Absent dramatic progress [in the next three months], no U.S. administration since 1945 will have left office with the Middle East consumed by such turbulence. In many ways, the Middle East is now a contested territory with the role of the U.S. undefined, while at the same time, thousands of U.S. military personnel face lethal threats from Iranian missiles and drones, and the Pentagon expends billions defending partners without achieving deterrence to our adversaries.
Despite the demands of the threats from China and Russia, the next administration must invest considerably more diplomatic and policy resources to restore stability in the Middle East and avoid a broader war.
Doyle: I believe the U.S. needs to lead urgent efforts with nations that recognize Israel and quickly offer ways to fill governance and security vacuums – in Lebanon, in Gaza and in the West Bank.
Corn: People in Washington had better be thinking, What is our plan?
What is our plan if we start to see destabilization in Iran? What if Iranians take to the streets and demand change – what are we going to do? And in Gaza and Lebanon, the Israelis have to have a plan. We have to have a plan. What's going to fill the voids being created? You can't create a void and then not be ready to fill that void very quickly.
There may be an opportunity here, as I have said about Lebanon, where the Lebanese people now have an opportunity with Hezbollah being decimated to take their country back.
But whatever the next administration is going to be in the United States, whether it's the Democrats or the Republicans, they have to have a plan to fill these voids because you probably have terrorist groups ready to fill in.
A way forward?
Roule: The coming days will tell whether the Gaza war may wind down, or whether it is beginning a new phase of grinding violence. Diplomats will certainly test whether hostage talks can restart. The prospect of Palestinian Authority governance of Gaza now seems a bit closer. Likewise, we seem to be approaching the point where we will see if it is possible to break the social hold of Hamas’ ideology much as the world did with al-Qaeda.
In the short term, Netanyahu and his hardline government have achieved a signal victory: the destruction of Hamas and Hezbollah leadership. The Prime Minister’s political survival looks strong in the near term. If this success produces a dynamic that frees hostages and the disarming of Gaza, Netanyahu will have achieved a historic success and overcome many of the political consequences of the Hamas attack of 2023.
But if the hostages remain in Gaza and the war drags on, the glow of this success will quickly fade.
Ideally, conditions in Gaza would improve to the point where Israel could feel safe to declare an end to the conflict, and an international security force would arrive in Gaza to assist a reformed Palestinian Authority in beginning the long road to recovery. Hezbollah would then have a face-saving opportunity to stand down, to recover while retaining its power in Lebanon. Iran would likely support a ceasefire, if only because it would allow both Hamas and Hezbollah to survive.
Unfortunately, this scenario would require a series of complementary decisions in Gaza, Doha, Jerusalem, Beirut, Tehran, and Washington. Arranging such a constellation will be challenging, to say the least, while the Gaza and Lebanon conflicts rage on and Washington passes through a difficult election period.
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