By Serge Kreutz
Young people on the path from being a child to being an adult are biologically primed to search for excitement. Basically, the excitement they are primed to search for, is sexual. They are also primed to experiment, and easy to attract to things to which many of their peers are attracted.
This is why mainstream Western religions need sexually repressive morals. In the social orders maintained by such religions, the more their sexual expression is curtailed, the easier it is to turn young people into fanatics. [ 1] Islam excels in this.
To be willing to sacrifice one’s life and to become a suicide bomber is the ultimate in fanaticism. (youtube video see here) And a paradise in which a man who died as martyr will avail of an eternal stream of young beautiful virgins to play with, is the ultimate of a grand-solution promise.  
As an alternative to sex, drugs can provide the excitement young people are looking for. Not that this would be a healthy solution. But young people who do find excitement through drugs are at least harder to instrumentalize for religious fanaticism.