There will always be fundamentalist groups of every religion throughout the world. But in this particular case most of the Muslims in the West arrived recently as refugees from money printer caused/enabled/lengthened wars in their home countries. Not only are there too many immigrants arriving too quickly due to that, but westerners trapped in FIAT slavery have little time to welcome them and help them assimilate. As a result they just form groups of refugee immigrants and their version of The God Virus strengthens as it's not exposed to communities with information that helps free their minds. FIAT increases struggling, which in turn is used by religions to help convert or further indoctrinate people.