I have long had a theory that the popularity of Christianity has always depended on its appeal to the sadism of its adherents. The exceptional should be crucified, saith Society; and somehow everyone suspects (in spite of all arguments to the contrary) that if there is a God, he may be exceptional in some way. So the figure of Christ crucified becomes the figure of the dangerous exceptional alien-suitably defeated. 'Only a suffering God can help', said Bonhoeffer, licking his lips.