This brings me to my next point: there is no Islamic pope who can speak on behalf of all the faithful, and in the majority Sunni tradition no ecclesiastical hierarchy that might constitute an Islamic version of "the Church." Occasionally I hear Al-Azhar, the ancient university in Cairo and the leading center of Sunni tradition, likened to the Vatican, but this is inaccurate. Islamic sheikhs and imams are not analogous to Christian preachers or priests or Jewish rabbis. In Sunni Islam, a sheikh is a religious scholar, and an imam is one who has been chosen to lead the believers in prayer--a selection resulting from the imam's knowledge of the Qur'an, his age, and his stature within the community. Sheikhs and imams do not act as intercessors, and Muslims are under no obligation to obey them. The individual's relationship with God is a direct one. Some Muslims may be better qualified to interpret Muslim doctrine or practice--the traditions of scholarship surrounding the Qur' an are multiple, complex, and ancient--nevertheless, all Muslims are fundamentally equal.
Somewhat ironically, it is this sort of decentralization of authority that may account for part of the reason that Americans and Europeans believe that Muslim leaders have failed to speak out against terrorism. In fact, Muslims have--but such statements arrive from many quarters. After 9/11, after the bombings in London, Madrid, and elsewhere where innocent blood has been spilled, Muslims have issued condemnations.
[Note: When she says, "Christianity" or "the Church," she's referring to Catholic Christianity.]