The Shiite community has much more religious coherence than its Sunni counterpart. This raises several questions for Sunni authorities, including the ones raised by prominent Iraqi Sunni cleric Sheikh Ahmad al-Qabisi in response to Ali al-Sistani’s fatwa regarding the need to defend Iraq against extremist Sunni attacks. “Shiites have a strong authority that orders and is obeyed. However, Sunnis do not and will not have a similar leadership or authority,” he said.
The religious Shiite institution has never had a clerical system such as the Catholic Church in the Vatican. However, it does have a strong bond with its popular base and can mobilize millions by issuing a single fatwa. The Shiite authority has a prominent historical role within Shiite communities through the social and spiritual power that the religious leadership has over its followers.