Kishk calls it "cultrural invasion", I think it's more like CULTURAL EROSION. "Fundamentilism" has been the response to the inclusion of Muslims in the capitalist system led by the west and Islam has been lost in the process.
Another reason is the failure of the nationalist secular èlite who have long been puppets of the west and have with time come to despise their own people. Thinking of them as being "backward". They have in way tried to dissolve the heritage and old traditions of their people and tried to replace it with western-modernisation (westernisation). Mustapha Attaturk and Pahlavi Shah are extreme examples of such leaders.
Just Cause,
Nice to see you.