Photo by Justin Palmer / Getty Images I can only speak for myself: the old joke is that one Jew on a desert island would need two synagogues: one to pray in and one to refuse to set foot in. I am an irreligious minor-public-school bourgeois Jew, and my common anxiety is that I am neither British nor Jewish, but a poor impersonation of both. Except this week I feel utterly Jewish, and I am not surprised that paint is thrown at Jewish primary schools, that Jewish students are too frightened to gather at vigils for Israel, that posters of...