The Iranian regime has demonstrated notable resilience since the February 2026 U.S.-Israeli strikes that killed Supreme Leader Ali Khamenei and other senior officials, with authority transferring rapidly to a hard-line successor amid ongoing conflict. Large-scale protests that began in late 2025 and escalated into 2026 faced decisive security force crackdowns, resulting in thousands of deaths but no widespread elite defections or institutional collapse. Recent diplomatic efforts, including Iran's September 2026 proposals for a short-term ceasefire and Strait of Hormuz reopening in exchange for sanctions relief, reflect continued negotiations rather than systemic breakdown, even as U.S. sanctions and blockades intensify economic strain. Traders assign an 83.5% probability to regime survival through mid-2027, consistent with the Islamic Republic's history of withstanding leadership transitions, external pressure, and domestic unrest without immediate disintegration.