The world changed on Saturday morning with Hamas’s attack on army bases and civilian communities in Israel. What began as a Palestinian military triumph became, within minutes, the greatest single atrocity of the entire conflict to date, by either party.

Every assumption of the status quo ante has been swept aside, including much of the international etiquette around calls for restraint: Israel appears to be hours away from launching the most overwhelming assault on a modern city since Vladimir Putin’s attack on Grozny, with unreserved Western blessing.