A new billboard at Valiasr square in Tehran shows the late Ruhollah Khomeini, left, looking on as the late Ayatollah Ali Khamenei, center, passes an Iranian flag to to his son, Mojtaba Khamenei, now chosen as Iran’s new supreme leader, on Tuesday, March 10, 2026. When U.S.-Israeli bombing began overnight in Tehran, some residents described the strikes as among the worst they had experienced since the war started. (Arash Khamooshi/The New York Times) By LEILY NIKOUNZAR and ERIKA SALOMON When…