I believe I understand what you mean by Iran's Supreme Leaders Fatwas.
Dont worry I am Sunni.
I will not try to justify his or anyone's Fatwas. And just to remind you Islam is not just a religion. It is also a code of life, code of conduct. It has given us rules and laws, It also tells us how to punish those who break those laws.
The most important fact Faith has to be without reasoning. (sometimes when I cannot reason I use the statement to convince myself).
Fatwas, Mullahs and the people can be an interesting topic for a book.