Iran's Supreme Leader Ayatollah Ali Khamenei waves to his supporters during a press conference after casting his ballot for the parliamentary runoff elections in Tehran on May 10, 2024. | Atta Kenare/AFP via Getty ImagesIn the weeks leading up to the latest US-Israeli airstrikes against Iran, there were reports that President Donald Trump’s administration was considering targeting Iran’s senior leadership, including Ayatollah Ali Khamenei, and Khamenei himself appeared to be preparing for the end. Still, the fact that the supreme leader was killed in his home office in an airstrike on the very first day of the war is a stunning development — the overnight elimination of one of the central figures in global politics for the last four decades.Born in humble circumstances in the northeastern city of Mashhad in 1939, Khamenei rose to prominence as a follower of Ayatollah Ruhollah Khomeini, the leader of Iran’s 1979 revolution, and served two terms as president in the 1980s before succeeding Khomeini as supreme leader after his death in 1989. Though seen as something of a moderate before he took over the most senior position in the Iranian regime, Khamenei’s rule was highly oppressive, particularly for Iranian women. His tenure included the crushing of several large protest movements including the 2009 Green movement, the 2022 “Woman, Life, Freedom” protests and the mass movement that broke out in January.He oversaw the construction of an “Axis of Resistance” of governments and proxy groups pushing back against US and Israeli influence in the Middle East — particularly after the 2003 US invasion of Iraq, when Iranian-backed militias fought US soldiers — and Iran’s ultimately ruinous nuclear enrichment program. But he also gave his somewhat reluctant approval to the 2015 nuclear deal with the United States and other countries — a decision he later regretted after Trump pulled out of the agreement.It will take some time to sort through Khamenei’s legacy for Iran and the wider region, and to understand the significance of his death. But to sort through some of the initial implications, Vox spoke with Alex Vatanka, a senior fellow at the Middle East Institute and author of the book The Battle of the Ayatollahs in Iran, which examines how the Islamic Republic’s backroom rivalries and leadership struggles have shaped its approach to the world. This conversation has been edited for length and clarity. These airstrikes didn’t exactly come as a surprise. We’ve all been anticipating them for weeks. So what does it tell us about Iran’s preparations that the supreme leader was killed on the very first day of bombing?A couple of things. One, [the Iranians] obviously didn’t do anything significant in terms of stopping the infiltration of the state machinery by the US and Israel. Presumably after the 12-day war, that should have been the big message. But given that senior members are being taken out as we speak, that suggests to me that they just couldn’t get their act together on that front. Then there was clearly miscalculation on their part, also, in terms of reading Trump’s intentions and Israel’s intentions.I don’t know what to make of Khamenei meeting senior folks in his office. That almost seems like he was asking for death. He had been talking a lot about martyrdom in recent speeches. But fundamentally, this was a regime that, when it came to the big test — its ability to stand up to the United States — spoke louder than its actions would allow.How inevitable was it that he’d get to this point? Are there steps Khamenei could have taken to avoid this outcome?For 37 years, basically, he was on one trajectory: “It’s my way or the highway.” He starts off back in 1989 as a 49-year-old, pretty insecure figure. He had had a very insecure presidency. He didn’t think he would be able to manage to stay at the top, and the shoes he had to fill after Khomeini were huge. Then he spent 37 years trying to prove to himself that he could do it. But he always chose force and coercion and repression as his method of keeping himself at the top of the power pyramid where he had ample opportunity to listen to his own people. Forget the US, forget Israel. He could have begun with listening to his own people. He was a very dogmatic speaker. He had his version of Islam that he believed in. He ostracized the vast majority of Iranian society. He created small pockets of supporters, and to him that was good enough and they would be his foot soldiers. I mean, going back to 1991 and all the way on to today, there was protest after protest after protest; people yelling, shouting, “This is not how we want to live our lives.” And he just refused to listen to them. He chose to fight at home, most importantly, but also abroad, which fundamentally brought him to this end. But he did it, seemingly, with his eyes open. So absolutely, yes, he could have been alive today. He didn’t have to go this way. How much of that do you think was the Islamic Republic’s governing ideology, and how much was just this one man’s personality?He was the one shaping the ideology. Obviously, he inherited a lot of things from his predecessor, the anti-Americanism, the stance on Israel, the forcing people to embrace this militant version of Islam. These are all things he inherited. But he could have softened it. If Khamenei had not become supreme leader in ’89, say it was someone like [cleric and former President Akbar Hashem] Rafsanjani, who came to a conclusion later in life that he needed to soften up, Iran could have been a very different place.A lot of this is rooted in domestic rivalries. The people who stood up to Khamenei were by and large what we would call “reformists,” so Khamenei had to carve out an alternative political identity. That’s why someone who in the 1980s was seen as a pragmatist, becomes a hard liner. He empowers the [Revolutionary Guard Corps]. He gives power to the security forces. He becomes a proponent of draconian policies like this forced hijab, the idea of fighting the Americans, fighting Israel, investing in the Axis of Resistance. All these are rooted in political rivalries. That was not his destiny, and now it’s what led to his demise. Is there one particular decision you’d point to that defined him?Of his 37 years in power, the last 22 years have been pretty much dominated by the nuclear issue. He could have gone about it in a very different way. He could have adopted a different political rhetoric. He wanted it both ways. He wanted to talk about being this anti-status quo power. He took pride and joy in standing up to the United States, in saying that the US can’t do a damn thing. The domestic opposition were then labeled as stooges of the foreigners. So much of this bravado was unnecessary, and it turned out to be empty. He thought the IRGC would save him, but the corruption and all the mismanagement of the IRGC is the reason you have a state in such disarray.The big gamble in the foreign affairs arena was that the Russias and Chinas of this world will come to his aid. It totally turned out to be a lie. But his biggest miscalculation was that he refused to look at his own people and accept that the people he was ruling over didn’t really have much sympathy, or didn’t even understand this worldview, this seeking martyrdom, whatever the hell that means. I guess the word is hubris here. The man really thought he could outsmart everyone. Clearly, many Iranians are happy to see Khamenei gone, as shown by the celebrations we’re already seeing. But do you think it matters politically that his removal was the result of a US and Israeli attack rather than forced by Iranians themselves?Well, the Iranians, the majority of whom wanted this guy gone one way or another, are thankful. But I think you also have lots of questions. Like, Trump probably did this for Israel. Fine, we will take that, but does Trump have a game plan after this? And obviously, much will depend on what happens on the ground. If you get more civilian casualties, if some of these strikes inside Iran become indiscriminate, like we’ve already had with this girls’ school being hit, that could have a serious impact on public sentiment. There was an announcement today of the formation of a three-member interim council to handle Khamenei’s duties for now and oversee the transition to new leadership. Do you think this is a regime that can regroup, particularly under the current circumstances?If the external pressure goes away, it’s likely that they can continue cracking down and killing their own people. But that’s the big question mark: How much appetite does Donald Trump have to stay in this? The Israelis want to stay, but their resources are limited. So the decision by the US is key. One thing to consider: if the CIA is in Iran and can track exactly where Khamenei is and give that information to the Israelis, that tells you they have a lot of assets and capacity on the ground. Can they use that capacity to create defections, to create some sort of acceptance [among senior leaders] of a need to end the Islamic Republic? That’s one option. The more hopeful option for the opposition is someone from outside the regime taking over, which, I think, is what the majority of Iranians want, but there’s a long way from wanting something to having something. And I’m not sure if there is appetite in the White House for what it requires to help these people organize from the outside to take over. The other bad scenario is that [the interim government] stays in power in pockets, including Tehran, but in the rest of the country, you have the pockets that emerge as semi-independent, kind of like Kurdistan [in Iraq].Who are the figures in the regime we should be watching as a potential successor?One is someone I wrote a profile on six years ago. His name is Alireza Arafi. [A senior cleric and protege of Khamenei, Arafi is a member of Iran’s powerful 12-member Guardian Council.] He’s the most likely in this three-person interim council, with [President Masoud] Pezeshkian and [Supreme Court Chief Justice Gholam-Hossein] Mohseni-Ejei. I have no idea in terms of whether he’s going to be the one. The formal way of doing this is to hold a gathering of the Assembly of Experts [the body tasked with selecting the supreme leader], but just logistically, that’s not likely to happen. Nobody’s going to ask 88 old men to show up in the middle of a war zone. So you got the interim council for now. And of the three, Arafi is the one who has been groomed by Khamenei. Whether that’s a good thing or a bad thing, time will show.