Israel and Iran are waging an existential battle. What does it mean for the US?: ANALYSIS When did Khamenei come to power? Kham

As the US weighs joining Israel’s assault on Iran, questions are mounting over whether such an intervention could trigger regime change in Tehran – an outcome that risks splintering the country and sending shockwaves across the region.

Iran’s supreme leader crushed internal threats during more than three decades in power. Ayatollah Ali Khamenei entrenched the system of rule by Shiite Muslim clerics.