TEL AVIV, Israel — A rabbi with a blowtorch climbs onto a scissor lift and is hoisted up to a giant Hanukkah menorah. "Are you ready!?' he asks the children gathered below. "Yes!" they shout in unison. Rabbi Shaul Reizes uses the blowtorch to light the first, rightmost candle and leads the children and a crowd of grownups assembled behind them at Habima Square in Tel Aviv in singing the Hanukkah blessings. It was at a ceremony like this one, thousands of miles away in Australia, where two gunmen opened fire on Sunday, killing at least 16 people, including a...