The Israeli claim of killing Iran’s top security official Ali Larijani, if confirmed, would mark the most consequential setback for Iran since the assassination of Supreme Leader Ayatollah Khamenei at the start of the US-Israel war on the Islamic republic, which is now in its 18th day. Larijani is one of the few remaining figures who straddle the political, security and diplomatic layers of the Iranian system at a time of war. He is not merely a senior insider, but part of a small cohort that can reconcile competing power centres within the state and translate battlefield developments into coherent political signalling. His role extends beyond messaging to quietly shaping external engagement, including maintaining channels that could, if required, support de-escalation. His loss, if confirmed, would not fracture the system. It would rather narrow the space within which strategy is formulated, tilting the balance further toward a security-driven approach and reducing flexibility for any future political exit. ...