Why did the Iranian regime not collapse after Khamenei’s assassination? US-Israel war on Iran

It is not true that the assassination of Iran’s supreme leader, Ali Khamenei, means the immediate collapse of the regime.

The conclusion is a hasty study, reflecting more wishful thinking than serious analysis. Yes, we are witnessing a seismic shock, the deadliest to hit the Islamic Republic since its founding in 1979. But the more important political question is not: “Is the shock detrimental?” Rather: “Was the system designed in a way that allows it to absorb a shock of this magnitude?”

The evidence available so far points to the fact that the system was not designed from the beginning to be a mere shadow of any one person, no matter how high his position.

The Islamic Republic is not an autocratic regime like the familiar Arab context, where the entire structure collapses if its head disappears. It is a complex ideological and securitised system with a religious head, beneath which lies a network of concrete institutions – some constitutional, some security-related, some bureaucratic and economic – working not merely to serve the individual, but to preserve the entity.

For this reason, the assassination of the supreme leader neither automatically eradicates the state, nor brings down the regime merely by virtue of the event; Rather, it shifts the crisis from the question of “survival of the head” to the question of “inner harmony”. The struggle to maintain it is the real danger.

The Iranian Constitution itself was drafted keeping in mind the possibility of a power vacuum. Article 111 states that a Temporary Council assumes leadership powers when the position becomes vacant until the Assembly of Experts elects a new leader as soon as possible.

Following the announcement of the leader’s assassination, powers were temporarily transferred to a three-member council, consisting of President Massoud Pezeshkian, judiciary chief Gholam-Hossein Mohseni-Ezei and Guardian Council member Alireza Arafi.

Meanwhile, the election of the new supreme leader was in the hands of the Assembly of Experts, which is made up of 88 members.

We can describe this clarity about how to deal with a leader vacancy as a “survival protocol” designed to provide the system the ability to continue even at the moment of maximum shock.

But an even bigger mistake would be to simply betray the constitutional structure. Yes, text matters, but the balance of power matters more. Here we have to distinguish between three layers from which the system derives its strength.

The first layer is religious legitimacy, represented by the Office of the Supreme Leader, the Assembly of Experts, and the Guardian Council. This layer provides the system its theoretical legitimacy and determines who has the “seal of legitimacy”. Therefore, the fight for succession is not only administrative but also religious and political at the same time.

The second layer is the security-military sector, led by the Islamic Revolutionary Guard Corps (IRGC), which is actually the backbone of the system, not just one of its institutions.

The third layer is the political bureaucracy, meaning the government, the presidency, the judiciary, and the administrative and economic machinery that keeps the daily functioning of the state running and prevents the scene of general collapse.

Among all these layers, the one that is really decisive is the IRGC.

Recent reports indicate that, following Khamenei’s assassination, the main question is no longer, “Is there a constitutional mechanism?” ” But rather: “Will the IRGC remain united?” This is because this institution is not under the president, nor is it a conventional army. The IRGC serves as the de facto guardian of the revolution, maintaining control over internal security, regional decision-making, and economic and influence networks.

Due to the war and the assassination of senior commanders, the IRGC has tightened its grip on decision-making in the country and has begun to rely on a degree of operational decentralisation that allows mid-level leadership to continue to operate quickly.

This situation means that even though the blow may have been to the head, it has not paralysed the limbs.

Based on current indications, it is difficult to say whether this war alone will result in the collapse of the Iranian regime. In fact, some signs point to the opposite: ideological regimes, when faced with an external existential threat, may harden rather than collapse, and targeting the supreme leader may lead to a more hawkish stance and defensive solidarity in the short term, rather than rapid disintegration.

Even some elements of the Iranian opposition abroad have clearly stated that bombings alone do not bring about the regime’s fall and that if any real change is to occur, it requires much broader internal mobilisation than mere military strikes.

However, the absence of immediate collapse does not mean safety. The regime may not collapse, but it may become war-weary, wary and more closed in on itself – especially after the selection of Mojtaba Khamenei, the son of the late supreme leader. In my view, this outcome is by far the most likely scenario: the regime will remain in place, but in a harsher, less self-confident form.

War not only tests deterrence but also reveals the extent of internal weakness and reshapes centres of power. When a regime emerges from such a war, suffering from losses and facing threats, it opts for the security option: it turns inward, expands suspicions, narrows the political sphere, and treats opponents and dissidents as “potential breaches” in its existence.

This trend has already started appearing. Reports have indicated that internal rifts have emerged due to the pressure of the war, particularly between hardliners close to the IRGC and those relatively less aligned with President Pezeshkian’s positions, especially after the controversy surrounding his comments about ceasing attacks on Gulf countries.

Some radical clerics within the system pressed to hasten the choice of a new supreme leader, suggesting discomfort with real power being temporarily distributed among a three-member council in the midst of an open war. These are not signs of collapse yet, but they are signs of concern within the structure itself.

Again, the dilemma is not the absence of a mechanism but the environment in which this mechanism is being tested: war, assassination, external pressure, military losses, divisions within the elite, and fear of defection.

In short, the Iranian regime is unlikely to collapse rapidly, but it will probably emerge from this war less unscathed than before. The most likely outcome is that it will persist, but at a higher cost: greater reliance on the IRGC, less room for politics, increased sensitivity to the opposition, and a stronger inclination toward internal security contraction.

In other words, this war may not end the regime, but it may eliminate its remaining flexibility. When regimes lose resilience, they may forcefully extend their lives, but at the same time they begin to slow internal drain. This is the current Iranian paradox: a regime that has not fallen but is entering a new phase of worrying rigidity— rigidity that may protect it today and weaken it tomorrow.