I think there is quite a distinction to make between an Islamist and a Muslim. I would say:
Don't fear the man of many books, but the man of only one book.
As soon as a religion is promoting inequality between the sexes or is advocating hurting people, I will critizise it, no matter how the religion is called. AND I will surely not speak for "German nations" in this place.
Finally you are quite wrong about your assumption about the disputes ... MOST are rooted in or at least justified by religion.