"The Shi'ah problem is probably the most formidable in this country. We were discussing it last night at an extremely interesting dinner party in my house... 'Abdul Majid said "What are you going to do if the chief mujtahid, whose voice is the voice of God, issues a fatwah that no Shi'ah is to sit in the Legislative Assembly ... or when a law is being debated, suppose the mujtahid cuts in with a fatwah that it's against canon law and must be rejected, irrespective of other considerations?" Imagine the Pope excercising real temporal authority in Italy and obstructing the Govt at every turn, and you have the position.
The remedy is, over time, that which has been found in Italy. Pope and mujtahid end by being regarded merely as silly old men; but we haven't reached that stage here yet. But if you're going to have anything like really representative institutions - always remember that the Turks hadn't; there wasn't a single Shi'ah deputy - you would have a majority of Shi'ahs. For that reason as 'Abdul Majid wisely said, you can never have 3 completely autonomous provinces. Sunni Mosul must be retained as a part of the Mesopotamian state in order to adjust the balance. But to my mind it's one of the main arguments for giving Mesopotamia responsible govt. We as outsiders can't differentiate between Sunni and Shi'ah, but leave it to them and they'll get over the difficulty by some kind of hanky panky, just as the Turks did, and for the present it's the only way of getting over it.
I don't for a moment doubt that the final authority must be in the hands of the Sunnis, in spite of their numerical inferiority; otherwise you will have a mujtahid-run, theocratic state, which is the very devil," - Gertrude Bell, October 3, 1920.