Together with Gilles Kepel and John Esposito, Olivier Roy completes the holy trinity of Western Islamo-sages. This book befits that status. Roy ranges widely in search of examples, from the ancient world to the forgotten corners of the present, setting them all to the music of his crowning argument: that religion is becoming 'deculturated', separated from culture. 

For Roy, secularisation and radicalisation follow in a vicious cycle. Religion realises it is not coterminous with the surrounding culture and moves to define itself independently. Red lines are drawn which reinforce fundamentalist doctrines and abjure leniency. Society, now separated from its religious backcloth, repays the favour by