Some Sunni Pakis and Arabs publically cheered 9/11.
Iranians mourned and held vigils for the victims of 9/11 (even inside Iran). They have no sympathy for Saudi terrorists, who are their own dead-enemies.
A substantial segment of Iranians are not Muslim, nor are they Christian. They are pro-western in culture and eastern in religion. They are desperate - and have been for many years - to throw off the Muslim yoke.
Apparently the Mullahs in Iran are (magic) carpet baggers.