Iran’s President and Foreign Minister Killed in Helicopter Crash: Live Updates

But amid fears of instability at a time when the Islamic Republic faces internal protests, a weak economy, widespread corruption and tensions with Israel, analysts expect little change in Iran’s foreign or domestic policy. Mr. Khamenei has set the direction for the country, and a new president will not change that much.

The system is “already on a path to ensuring that the Supreme Leader’s successor is fully aligned with his vision for the future of the system,” said Ali Vaez, the Iran director of the International Crisis Group.

He described “a pretty tough vision” in which key areas of foreign policy, such as supporting regional proxy militias and developing components for a nuclear weapon, would not change.

Whoever is elected as the next president, Mr. Vaez said, “will have to be someone consistent with that vision, a submissive figurehead.”

Ellie Geranmayeh, Iran expert at the European Council on Foreign Relations, also sees continuity in important foreign policy issues, including regional issues and the nuclear program. “These files were under the control of the Supreme Leader of Iran and the IRGC,” she said, referring to the Islamic Revolutionary Guard Corps, “with Raisi having little influence during his term as president.”

“Raisi was certainly useful to some IRGC factions,” Ms. Geranmayeh said. Unlike his predecessor, Hassan Rouhani, Mr. Raisi, a more conservative loyalist, “has not challenged the IRGC on either domestic or foreign policy issues,” she said.

But criticism of Mr. Raisi’s performance as president has already raised questions about whether he is the best candidate to succeed Mr. Khamenei, she said.

Mr Raisi’s main rival was seen as Mr Khamenei’s son Mojtaba, 55, whose candidacy was damaged by the aura of a monarchical succession.

Mr. Raisi’s death could make it easier for Mojtaba Khamenei to succeed his father. But the inner workings of Iran’s religious and domestic politics are deliberately secretive, and the decision is ultimately made by a council of senior clerics known as the Assembly of Experts. Although Mojtaba Khamenei is considered the clergy’s favorite, they could still choose to elect one of their own leaders or adopt a more collective leadership.

His father, the supreme leader, had worked hard to “reduce the unpredictability within the system by grooming President Raisi as a possible successor, and now all those plans are out the window and back on the drawing board,” he told Mr. Vaez .

The external challenges are also great. Iran and Israel attacked each other directly in April, even though Israel is already fighting Iran’s military proxies – Hamas in Gaza and, less explicitly, Hezbollah in Lebanon. Iran also supports the Houthis in Yemen, who have attacked ships in the Red Sea.

Iran has worked to avoid a major war between Hezbollah and Israel, and the Islamic Republic can ill-afford direct conflict with Israel either.

It is holding intermittent talks with the United States about de-escalating the regional conflict and the future of its nuclear program. Mr Raisi’s death also threatens to complicate these talks.

“While there will be no love for Raisi in D.C., the instability in Iran would come at a bad time,” said Trita Parsi, an Iran expert at the Quincy Institute for Responsible Statecraft, making “preventing escalation all the more difficult.”