I have hesitated for days to dip a toe in here. I began teaching in 1972 in Bradford (my home town) and continued (with children breaks) until 2002.
On realising that most pupils entering school were Muslims, I bought a copy of the Koran (Q'uran) and read as much of it as I could stomach. I did give up before the end - sickened by the medieval, male sexual fantasies which it contained. I don't claim to be a scholar on this subject (some of you obviously are) and can only speak as to my real-life experience.
In the early 1970's I had some lovely Muslim pupils who came from supportive and inclusive families. We talked about religion with no problem about the differences and agreed about all the common points (Peoples of the Book).It gradually became worse.
In the late 1990's, when I was teaching in a large comprehensive in Bradford, a non-uniform day suddenly became a day when the boys arrived in Arabic garb and waving the Islamic flag (the last non-uniform day we had), also, about that, time I was shouted down in an R.E. class ( the subjects were on an agreed multi-faith Bradford curriculum) and told that only Islam held the truth. It got worse.
I have so much more knowledge that I cannot communicate here (it needs a book) - but my very sad, indeed horrific, conclusion is that eventually there will be a religious war. This is awful from all sides, I knew many good Muslims who are probably equally horrified.
Well, I'm new to the answer bank so If I'm out of turn I apologise - but I know more than most about the reality.