For years, I’ve lived with the question, “what gives an artist the right to speak out?” Now another question is inescapable — what gives an artist the right not to? Both are important questions. Both are relevant to us as Jews.

In our talmudic history, music has both private, spiritual uses — the songs of David, the early mention of the kinnor, the lyre — and a political or martial role — the call to arms of the shofar. Ah, but music is one thing, those who play it quite another. This goes for the arts in general.

Take two controversial recent cases. Nigel Kennedy hit the Proms in mildly confrontational mood when he brought the young players of the Palestine Strings to mash up musical styles around Vivaldi’s The Four Seasons. I wasn’t there, but have heard that he made some passing remark on “apartheid”. An audience member reportedly yelled out something not printable in a family newspaper. That was it.

But the fall-out has been rather fascinating, in the way that watching a pile-up on the motorway might be fascinating. The BBC edited out Kennedy’s statement for the broadcast repeat and online; then my respected colleague Norman Lebrecht reprinted on his blog an open letter purporting to be from the violinist, castigating the Beeb for its “censure” and suggesting that sinister outside forces might be at work.

After which, Kennedy’s manager hastily got in touch to say that, no, Kennedy had never written any such thing and that the BBC had clearly explained beforehand that political statements were not allowed at the Proms.

That wasn’t the end of it. Pink Floyd’s Roger Waters denounced the BBC “censorship” of Kennedy, and called on fellow musicians – his “brothers and sisters in the family of Rock’n’Roll” — to boycott Israel. This from the man who recently performed in Belgium with the image of a pig next to a star of David on stage.

So much for artists who do. Now to artists who don’t. President Putin has been creating a stir recently with his comments against homosexuality in Russia. Cue outrage. But not much from Russian artists. The soprano Anna Netrebko and conductor Valery Gergiev are among those who have come under pressure to condemn Putin. As yet, they have declined or stayed mum.

And, in something of a corker, film-maker Yuri Arabov, who has made a new biopic of Tchaikovsky, widely thought to have been gay, told a Russian newspaper: “I am opposed to the discussion of such themes, particularly in the arts.” He also denied Tchaikovsky was gay.

Should political themes be discussed in the arts, or by the artists? And those are two separate things. In the arts, well, Beethoven originally intended his Eroica symphony to be a gesture of admiration for Napoleon, Arthur Miller famously wrote The Crucible as a (not very) coded denunciation of McCarthyism and the musical Hair is anti-Vietnam War. So nothing new there.

But how about the artists? They have a public stage by virtue of what they’re good at. Why should a soprano like Netrebko comment on Russian politics, just because her voice has made her famous? Has she chosen to be the mouthpiece of Russian politics? By the same token, why should anyone care what Roger Waters thinks — he’s a musician, not a professional political commentator.

I once asked a well-known director, who was hosting artists’ political talks at the National Theatre about the Iraq war, why we should care what they think, simply because of their fame. “I get that,” he replied, “but then why shouldn’t I speak out if I want to say something? If people want to listen or not, that’s up to them.”

Fine, fine and I get that. But he had a theatre. It was not created for that purpose. Yet Shostakovich was blamed by many for apparently kowtowing to Stalin, Furtwangler for staying in Hitler’s Germany. Should they have left their countries, as others did? Would that have been enough?

Let’s be honest. I suspect we’re all ambivalent on this. When I was young, my family forbade me to join a school trip to see the Moscow State Circus because of Russia’s treatment of its Jews. Yet I heartily disapprove of anyone boycotting Israel’s artists because of what they see (even if I disagree) as its cruelty to Palestinians.

Are the arts, are artists, really above politics? If artists abuse their stages, I have no time for them. But for Kennedy to perform beautiful music with Palestinian musicians, wearing an Arafat scarf, OK, I respect that. If only he’d kept shtum.