I think that part of where American or Western predispositions towards women and Islam arise in not being able to fully dissect and understand the complexities and nuances of the Islamic faith. Like all religions, Islam is complex and these nuances are not fully grasped by much of how the West depicts or understands the religion:
...too often coverage of Islam and the Muslim world assumes the existence of a monolithic Islam in which all Muslims are the same.
This monolithic conception of the religion is evident in how the West perceives the actions of the Taliban. The Taliban did much to set back the Western understanding of Islam and its treatment of women. When women are publically chastised and stoned to death along with their heads being severed, it tends to resonate in the Western understanding. In this, the role of expect ions plays a large role in how the West understands the construction of women's roles in the Islamic faith.