Iran’s Leadership Crisis Deepens After Supreme Leader’s Assassination and Assembly Strikes

The assassination of Supreme Leader Ayatollah Ali Khamenei on February 28, 2026, triggered a constitutional crisis in Iran. The Assembly of Experts, a body of 88 Shiite clerics, endorsed Ali Larijani as interim leader. The interim leadership council, including President Ebrahim Rais, Head of the Judiciary Gholamhossein Mohseni Ejei, and Ali Larijani, holds temporary authority. However, the path to a stable transition remains uncertain. Israeli and U.S. strikes targeting the Assembly of Experts have intensified the crisis, disrupting its ability to oversee the selection of a new Supreme Leader.

Iran’s theocratic governance model, rooted in the 1979 Constitution, centralizes power in the Supreme Leader, who combines spiritual and political authority. The first Supreme Leader, Ayatollah Ruhollah Khomeini, was selected through religious consultation, setting a precedent for clerical succession. His death in 1989 led to the formal selection of his protege, Ali Khamenei, by the Assembly of Experts. This body, composed of members elected every eight years, has historically overseen the selection of Supreme Leaders. The Guardian Council, a 12-member body of clerics and lawmakers, vets candidates for public office, including Supreme Leader contenders.

The Supreme Leader holds ultimate authority over Iran’s military, judiciary, and foreign policy. The Guardian Council vets candidates for public office, including Supreme Leader contenders. The Expediency Discernment Council, which includes the Supreme Leader, president, and senior officials, mediates disputes between the Guardian Council and parliament. President Ebrahim Raisi, a Khamenei loyalist, and Mohseni Ejei, the head of the judiciary, have taken expanded roles in managing the transition. Raisi, elected president in 2024, now serves as interim leader. Mohseni Ejei oversees legal matters, while Larijani represents strategic and security interests. The interim council’s composition—spanning hardline and reformist factions—has exacerbated internal divisions. The Islamic Revolutionary Guard Corps (IRGC), a paramilitary force designated a terrorist organization by the U.S. in 2019, has emerged as a central actor, with figures like Ali Larijani overseeing strategic affairs.

Mojtaba Khamenei, the Supreme Leader’s son, is a leading contender for the succession. A 56-year-old Shiite cleric, he has never held a formal government post but is believed to have strong ties to the IRGC and clerical networks. His candidacy reflects hardline faction preferences for ideological continuity. Other potential candidates include clerics like Ayatollah Alireza Arafi and Mohseni Ejei, though none possess significant public support or national security experience. The Assembly of Experts, which has never publicly overseen the Supreme Leader’s decisions, now faces the challenge of balancing competing interests. The Guardian Council’s role in vetting candidates has historically marginalized reformists, reinforcing the dominance of conservative elites. This dynamic has shaped Iran’s political landscape, ensuring that leadership transitions remain tightly controlled by religious elites.

The succession crisis has intensified internal power struggles, with factions vying for influence. The IRGC’s growing role in governance, coupled with economic collapse and public discontent, has raised concerns about the regime’s stability. Analysts warn that further external military pressure could destabilize Iran further, with the risk of a ‘military takeover’ scenario akin to Syria’s Assad regime. Israeli and U.S. strikes targeting the Assembly of Experts have compounded the crisis, disrupting the body’s ability to function and exacerbating uncertainty in the succession process. Regionally, the loss of a unifying figure has fragmented Iran’s proxy network, increasing the risk of autonomous actions by groups like Hezbollah and Hamas. The conflict with the U.S. and Israel has already disrupted critical energy shipping lanes, including the Strait of Hormuz, driving up global oil prices. The international community, including Gulf states and European powers, is closely monitoring the situation, with diplomatic efforts to de-escalate tensions ongoing.

The transition to a new leader will determine Iran’s trajectory. While the regime has historically resisted significant reform, the current crisis may create opportunities for incremental changes. The Assembly of Experts could play a more active role in shaping the Islamic Republic’s direction, though the entrenched power of the IRGC and conservative factions suggests cautious, stability-focused reforms. Economic resilience will be critical in preventing further unrest. The regime’s strategy of a ‘war of attrition’ against the U.S. and Israel aims to build pressure toward de-escalation by increasing the costs of continued conflict. However, the broader implications for the Middle East and global energy markets remain uncertain, as the situation continues to evolve. The fate of Iran’s leadership structure hinges on the interplay between constitutional mechanisms, political factions, and external pressures. For now, the regime’s ability to navigate this transition will determine its survival in a volatile geopolitical landscape.