The shock and horror of the massacres by Hamas in southern Israel have only intensified as the days have gone by and the full extent of the violence has emerged. Young revellers slaughtered as they fled a music festival; babies murdered with their parents; the very young and old taken hostage. This atrocity may not be an existential moment for the state of Israel, as the Yom Kippur war appeared to be 50 years ago. But for Israelis, and for Jews worldwide, their belief in a homeland where they could be safe after centuries of antisemitic persecution lies in tatters....