Everyone knows that musicians are fearless dissenters, forever standing up for what they believe to be right. Just think of Bob Geldof, hoarsely assailing our consciences for Africa’s starving millions while Western governments look the other way. Or Dmitri Shostakovich, turning out symphony after symphony of coded rage against his Soviet masters.

Or Viktor Ullmann, the Czech composer who wrote a powerful and poignant operatic denunciation of the Nazis — The Emperor of Atlantis — while imprisoned in the sealed ghetto of Terezin. (He was killed at Auschwitz soon afterwards.) Or William Byrd, who might have been roasted at the stake for writing secret laments for his fellow Catholics when England was racked by antiPapist witchhunts. Or even Mozart, risking imperial censure in 18th-century Vienna by turning a shocking revolutionary play called The Marriage of Figaro into an opera.

But the very fact that I have cited five instances that are nearly always mentioned when people talk about “music and protest” demonstrates the real truth: that musicians are very rarely fearless dissenters. I don’t think that this implies a particular lack of courage — rather, that the nonverbal, nonvisual medium of music (unlike, say, literature, theatre or painting) isn’t particularly suited to conveying explicit political or sociological messages. True, a stonking great tune can give a boost to an otherwise simplistic revolutionary lyric: just think of La Marseillaise. But it’s the text that carries the message.

There’s another problem. Repressive regimes, of both left and right perversion, tend to favour safe, “traditional” music. So avant-garde musicians naturally line up with the dissidents. But the trouble with avant-garde music is that, by definition, few people understand it. Consequently, what’s intended as a hard-hitting protest often comes across as a load of obscure waffle. Case in point: practically any piece written by Karlheinz Stockhausen in the zany Sixties.

So is it worth attending next weekend’s Riot concerts of protest music in London and Manchester? Absolutely. I shall be the first to man the barricades! Not least because the show features the peerless Loré Lixenberg, multi-talented star of Jerry Springer — The Opera. But also because of the range of political concerns that will be displayed, from the Chilean composer Sergio Ortega’s denunciation of Pinochet, and Paul Fretwell’s meditation on the 1969 Stonewall rebellion by gay activists, to Frederick Rzewski’s evocation of the brutally suppressed Attica Prison riot in New York State, when 31 prisoners and hostages were killed.

But you have to ask: did any of these well-meant musical protests change the world? Many years ago, in bad old Bucharest, I reviewed a production of Verdi’s Nabucco. Afterwards the opera’s director, learning that I was a Western journalist, furtively approached me. “Did you notice what shape the cast formed when they sang the Chorus of the Hebrew Slaves?” he whispered.

“Weren’t they in a sort of bulging circle?” I replied.

He looked very disappointed. “It was the shape of Rumania!” he hissed. “That was my secret protest against our evil government.”

Hmm. With dissidents like him around, no wonder that Ceausescu survived so long.

Riot details: www.spnm.org.uk

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