Western societies have been going ever further in freeing their citizens’ choices — in releasing them from ties of tradition or religion, in allowing people to marry whom they want and divorce as often as they want, have sex with whom they want, die when they want and generally do what they want. There are few, if any, moral boundaries left.

In this context, radical Islam offers salvation, or at least purpose, in the form of a life whose moral parameters are strictly set, whose daily habits are prescribed, whose satisfaction of everyday needs is assured and whose rejection of freedom is unequivocal. By taking away freedom, the Islamic State lifts a psychological weight on its young followers adrift on the margins of European society.

Mark Lilla, in an essay this year in The New York Review of Books on the French novelist Michel Houellebecq’s “Submission” (whose central character, a disaffected literature professor, ultimately chooses to convert to Islam) made this important point:

“The qualities that Houellebecq projects onto Islam are no different from those that the religious right ever since the French Revolution has attributed to premodern Christendom — strong families, moral education, social order, a sense of place, a meaningful death, and, above all, the will to persist as a culture. And he shows a real understanding of those — from the radical nativist on the far right to radical Islamists — who despise the present and dream of stepping back in history to recover what they imagine was lost.”