Could you provide me with statistics regarding what fraction of the islamic world believes in which school of Islamic thought and their degree of openness/tolerance? I have also opened a thread in the Religious Debates section analyzing the saying in the Quran properly. You are welcome to contribute.
In Saudi Arabia my guess is 15 % are Shia. So a significant number of Saudis don't even believe in the books of the Sharia that many westerners think define Islam. In Yemen there is a civil War raging between Zaidis and wahabis (both are Sunni, but don't have the exact same books). So 50% believe in different leaders and different books in Yemen. In Iraq the Shia are a majority so don't believe in the sharia books.
Similarly, Islam in Ethiopia is Sunni, but evolved separately from the Arabs under a different figure, Najashi rather than Umayyads. so different, even though the books are the same
Similarly Sufi Islam has historically been very popular among people of Pakistan and India. In addition, rationalists such as Sir Syed became very powerful figures in India too. There is also 5-10% of Muslims in India and Pakistan are Shia
Unfortunately, after the soviet invasion of Afghanistan it became financially lucrative to join the violent jihadis and wage war on the Russians. The west looked the other way as Saudis radicalized the Muslim world by pumping million of dollars and encouraged the demonizing of non Muslims in newly opened schools (madrasas) so they would seek martyrdom in OUR fight against the Russians. Those who opposed the war on religious grounds and sought peace were socially and economically marginalized.
Once that war was won the propaganda continued and began to target other non Muslims such as Jews and Christians.
Then, there is Iran which is mostly Shia. So they don't believe in the Sharia books.
Then there is Turkey, Sunni with the same books, but Hanafi Turkish leaders (Caliphs) modified Sunni laws in the age of the Ottomans. So different. Sufi Islam is also very common in Turkey.