One of the most important distinctions between Shiite and Sunni belief is the profound respect of the imams. Most Shiites believe that there were 12 legal successors to Muhammad as caliph, and that the final imam, now termed the Mahdi, disappeared when he was lifted up in the hands of God. The Shiite lot believes the Mahdi will come back to earth one day and take the role of their savior. A war between the good and evil forces will follow, ending in a 1000-year domination of peace and the end of this world.
By latest research an estimated eighty five percentage of Muslims are Sunnis, thirteen percent Shiites and two percent members of other groups. Other than Iran, Iraq has evolved as a major Shiite government when they gained political dominance in 2005 under American occupation.
These two sects have always remained independent, coming into contact regularly only during the Hajj pilgrimage in Mecca. In certain nations like Bahrain, Iraq, Syria etc the two sects have mingled and married. Shiites have been treated rudely in several nations dominated by Sunnis, notably in Saudi Arabia. Some Sunnis have complained of ill treatment in the Imami Shiism dominated states of Iraq and Iran (Adherents.com, 2002).
As we all know Osama bina Laden belong to the Sunni sect. For him the end of the rule of the caliphs in the 1920s was a calamity, as he made clear in a videotape made after 9-11. On the tape, broadcast by Al-Jazeera television on 7th October, 2001, he said: "What United States tastes now is just a copy of what we have encountered. Our Islamic country has been suffering the same for more than 80 years, humiliation and dishonor, its sons martyred and their blood shed, its sanctities treated with contempt”