Our daily media diet of murder and massacre in the Middle East carries on the history of more than four thousand years. Readers with a regularly well-thumbed Bible will need no guidance to the scores of horrible examples set out in the Old Testament; others, perhaps able to retrieve a Bible from somewhere beneath the dust of a back shelf, may take (simply as a reference at random) the last two chapters (20 and 21) of the Book of Judges. There the ethnic cleansing of the day is illustrated by “smite the inhabitants of Jabesh-Gilead with the edge of the…