Even in a place where a violent form of Islam is culturally dominant, people in that place will understand their ideology as an oppositional, specific ideology. But in America, we will never understand violent Christianity, or violent white supremacy, as being an ideology at all.
I wish I had a vocabulary to talk about the layers of power you have to surmount to be able to take your ideology for granted as a non-ideology in the no-culture-all-culture.