I'm not a big friend of the Israel Philharmonic, an orchestra composed of too many Russians and no Arabs. But when I hear people calling for a ban on the IPO because it has "Israel" in its title - worse, when some of the noisiest objectors are self-avowed Jews - I shall be out on the barricades defending the orchestra's right to play.
Who are these protesters, anyway? Some are known to me as musicians and colleagues, though I cannot for the life of me figure out why a player in a London orchestra should want to outlaw a visiting ensemble. Imagine the outrage if the London Philharmonic were boycotted in Liverpool because of something Mayor Boris Johnson once said or wrote. That, in cold logic, is the equivalent to tarring the independent-minded IPO with the brush of Bibi Netanyahu – as the cellist Steven Isserlis argued this week in a letter in the Guardian.
The Jews who view Israel as the acme of evil are, on the whole, not the brightest beans in the basket. They tend to be single-issue sympathy tourists (Sists) whose naiveté is manipulated by Palestine spinners in the course of a short trip to the most deprived parts of the West Bank.
To witness suffering at close hand is a helpless ordeal. To have it blamed on your own kind is doubly disarming. Our Sists are faced with a Jenin ultimatum: either condemn your own or be yourself condemned. Damning your own is their route to redemption.
This is not a new phenomenon. In 1930, the philosopher Theodor Lessing coined the term "Jewish self-hate" (Jüdischer Selbsthass) to denounce alienated intellectuals who blamed the German Jewish community for the rise of Nazism. How? By behaving like Jews, living together, being too readily identifiable.
In much the same way, today's self-haters blame Israel and world Jewry for the unending misery of millions of Palestinians, oblivious to the peace deals ditched by Palestinian obduracy and the relief efforts made by many Israelis and Jews. Trapped in their tunnel vision, the Sists spout slogans and substitute emotion when logic fails.
One of the signatories to a musicians' letter of shame calling for the IPO to be banned from the Proms declares that his grandmother did not die in Auschwitz for Jews to act like this - as if her fate, shared by millions, grants him a singular moral superiority.
There is no arguing with such Sists. They are the Seder's youngest sons, the ones who don't know how to ask the questions they should have put to their West Bank guides. Speaking neither Arabic nor Hebrew, they inhabit a self-sustaining virtual reality, and rush to frame their fellow-Jews in a blood libel. Shame? The noun's not strong enough.