Iran’s Islamic regime has selected its new Supreme Leader: Mojtaba Khamenei. He is the son of Ayatollah Ali Khamenei, who was killed just over a week ago on the first day of the American-Israeli military campaign in Iran.

It is ironic that the Islamic Revolution, which swept to power in 1979 on the back of intense anti-monarchical sentiment, should become dynastic. Indeed, it might be suspected that the turn to a hereditary republic is so strange as to be a contingent wartime decision, perhaps forced upon the civilian-clerical establishment by the Islamic Revolutionary Guards Corps (IRGC). Not so. Mojtaba has been understood as the most likely successor since May 2024 when then-president Ebrahim Raisi was killed in a helicopter crash.

Mojtaba has deliberately kept to the shadows; most Iranians have never heard him speak, and he only appears publicly a couple of times per year on sacral days in the regime calendar. Yet it is known he spent time at the front late in the 1980-88 Iran-Iraq War, where he apparently forged his enduring personal relationships with IRGC leaders. After training as a cleric in the late Nineties, Mojtaba started working in his father’s office and was deputised to manage the 2005 and 2009 Iranian presidential elections, including the IRGC-Basij crackdown on the protests against the rigging of the latter.

It was around 2009, as Khamenei Senior consolidated a personal dictatorship underwritten by the IRGC, that claims surfaced of Mojtaba as “the gatekeeper for his father”. This influence over access to the Supreme Leader’s Office led to US diplomats calling Mojtaba “the power behind the robes”. An exaggeration, perhaps, but Mojtaba’s growing powers over the last 15 years have included such sensitive responsibilities as repressing further rounds of protests.

All the available evidence suggests Mojtaba is part of his father’s “Principlist” faction, the most extreme element of the regime that is anchored in the IRGC. Mojtaba has also developed an inner circle, drawn from the first generation brought up after the Revolution and composed of ultra-radical clerics. Notable among these is Alireza Panahian, an apocalyptic ideologue with a leading role in indoctrinating the IRGC.

It is telling that, although Mojtaba’s wife and mother were killed alongside his father, he was absent — kept separate because he is the mechanism for continuity. The central mission of the Iranian Republic that Mojtaba now leads has been confrontation with the West, which as the revolutionary clergy see it has two components. First is warding off what Khamenei Sr called the Western “cultural invasion” domestically — in other words, repressing all signs of liberalism and secularism. The second is exporting the Islamic Revolution in the region. In practical terms, that involves trying to destroy Israel, seen as a Western imprint, and subverting Iran’s Arab neighbours.

If defying America has defined the Islamic Republic generally, the choice of Mojtaba was in itself an example. President Donald Trump, hinting at a Venezuela-style solution to the Iran war, said yesterday that the new Supreme Leader is “going to have to get approval from us. If he doesn’t […] he’s not going to last long.” The regime’s response was to name Mojtaba, someone Trump had specified was “unacceptable” days earlier. A lot would now appear to depend on how well-hidden and fortified Mojtaba’s bunker is.