One of the strangest things about political activists is that they so rarely understand freedom, the very thing they think they are fighting for. Everyone in this country, even a sugar plum fairy, is entitled to freedom of thought and of speech under the law, but there are countless high-minded activists who do not think so. So it was that a group of Unite Against Fascism activists fetched up at the Coliseum in London on Friday afternoon to demonstrate against the fascist fairy, the “BNP ballerina” Simone Clarke.

She is an exceptional dancer who finds herself at the middle of an even more exceptional political drama. Having danced the role of the Sugar Plum Fairy in the Nutcracker over the Christmas season, she was soon afterwards exposed as a member of the British National party. On Friday she appeared on stage for the first time since the revelation of her political views in the role of Giselle, only to be booed and hissed by UAF agitators outside the theatre and even inside from the stalls.

“The principal ballerina is a BNP member,” they cried, before they were removed. “No fascism in the arts.” Clarke bravely danced on, however, like a real trouper, smiling throughout; I suppose ballerinas are used to smiling through pain. She was supported in her ordeal, whether she knew it or not, by a bizarre group of champions — 25 members of the BNP, including some of its top brass, and not perhaps your average balletomanes.

How I wish I had been there. All this might be serious in its way, but it is a delicious absurdity too. For one thing the English National Ballet has dancers from 19 countries, some of whom must presumably be immigrants, and possibly dark of skin; I would love to have seen the BNP neo-balletomanes’ faces as they watched these migrant swans leaping about in swathes of floating net and little wings, not to mention several men in pastel tights. How wonderful to think of the skinhead BNP top team supporting all this.

What the UAF activists are trying to achieve is to get Clarke sacked. The English National Ballet has resisted very properly; it has refused to comment on its principal dancer’s opinions, saying her views do not represent the ENB’s views, which in any case does not express any political view. The ENB is in a difficult position though, because it receives £6m of public money each year from the Arts Council, and this can and will be used by activists to put pressure on the company to distance itself from Clarke.

Bectu, the broadcasting workers’ union, is making this demand and Lee Jasper, the race relations adviser to the mayor of London, joined this lamentable demonstration, saying: “The protests will continue . . . English National Ballet have got a real fight on their hands.”

This is a strange story in every way. Despite her fear of mass immigration, Clarke has an immigrant boyfriend of Chinese-Cuban descent, also a dancer; there is a hint of inconsistency here surely, and the BNP certainly finds it a touch embarrassing. And then the protesters in the street, who say that ethnic English people’s fear of immigration is nothing but irrational racism, rather undermined their own case by shouting “We are Muslim, black and Jew, there are many more of us than you” — by this threat confirming that a fear of mass immigration is not merely irrational racism. Brilliant.

All these big bold men lined up against a single rather underweight woman; it is not an edifying spectacle. If only they had the intellectual modesty that she has shown. Explaining to a newspaper that she’d been drawn to the BNP by watching the news and by their manifesto, she said: “I am not too proud to say that a lot of it went over my head, but some of the things they mentioned were things I think about all the time, mainly mass immigration, crime and increased taxes.” The world might be a better place if more people were not too proud to admit that things are complex and difficult to understand.

It is clearly too difficult for Friday’s activists to understand that free speech is indivisible. Perhaps they have forgotten the McCarthy era in America, when performing artists, particularly in Hollywood, were outed, sacked and ruined for their pro-communist views (real or alleged). That was entirely wrong, I hardly need say. But there are plenty of people, including me, who think that pro-Trotsky, pro-Stalin, pro-Mao communism, and all kinds of views expressed by people in the arts to this day, are hateful and despicable, and, I think, a great deal worse than the BNP.

That has never prompted real lovers of freedom to try to silence them; real lovers of freedom accept that to repress one hated view is as bad as repressing its opposite. It will only strengthen the hated view; by contrast the openness of freedom will weaken it, if it is wrong, as the heroic JS Mill so eloquently argued.

Besides, why should anyone take the political views of artists seriously? I know that everyone does these days, and pop stars such as Bono are called upon to pontificate on matters of global concern. But the fact that they are famous and talented does not mean that their views are worth paying attention to (rather as the BNP ballerina’s views are of no interest).

There is no law of nature according to which artists must of their nature be rational, sensible and well judging; rather the reverse tends to be true, because the arts have to do with risk, danger, experiment, originality and inconsistency. They are born out of anger, resentment, joy, contrariness and wildness, with the result that few artists have ever been balanced and well-informed political or moral philosophers.

In fact if artists were judged on their views, theatres and galleries and bookshops would be almost empty. If sensible people had tried to bring down artists of bad and daft political views we would have had no Vanessa Redgrave and no Harold Pinter. Should we ban Brecht from the stage because of his support for the odious East German regime? Come off it.

People who loathe their views may love their talents. It is high time that liberals, luvvies and political activists started either to defend free speech, or stopped pretending to.

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