To any closed society, there are two things that represent a more deadly threat than a foreign army on its borders: liberal Western values and a global language that gives access to the outside world.

The British Council’s job is to promote both. Little wonder, therefore, that it has often been the target of governments determined to keep their populations cowed and in ignorance. Little wonder also that it has been accused of cultural imperialism, purveying propaganda or subverting the values of others.

Iran’s campaign against the Council betrays a fear by hardliners that Britain’s cultural arm will undermine their hold on the country. The values of liberal democracy — social tolerance, personal freedom, gender equality and political pluralism — are not those preached by the clerical establishment or the Revolutionary Guards. But in a country where public opinion, especially among the young, is overwhelmingly pro-Western and impatient of the restrictions imposed by religious dogma, the Council has found an eager response. Some 13,000 Iranians took part in programmes in Tehran last year. The hardline response, therefore, has been to silence the message — by denying visas, by bureaucratic harassment and finally by threats against those loyal Iranian staff keeping the Council offices open.

The British Council has seen this before. Twice it has been forced to withdraw from Iran. In 1967, rioters burnt the Council’s offices in Baghdad to the ground in protest at Britain’s perceived pro-Israel bias in the Arab-Israeli war. Two years ago, it suffered similar intimidation in Russia. After the fall of communism, the Council expanded rapidly, setting up a dozen regional offices. But in 2007 the Kremlin accused it of operating illegally by not paying taxes that were due. A propaganda campaign hinted at espionage, Russian staff were harassed, all but three offices were ordered to close and British staff were withdrawn. Effectively, the operation in Russia was suspended.

The pretext was the worsening political climate between Britain and Russia. The real reason lies deeper. Nationalists in Russia, as in Iran, are xenophobic and suspicious of the West. Cultural diplomacy represents “soft power” that is difficult to counter: Vaclav Havel, the former Czech President, has stated that as a dissident against communism he depended on the British Council for access to the outside world.

The teaching of English hugely increases that access. Anyone learning a language imbibes an interest in its native speakers and a sympathy and enthusiasm for their values. English also opens doors to all the subversive sources available on the internet. Little wonder therefore that China tries to monitor how its citizens use their English skills when searching the web.

What of the accusations of propaganda and cultural imperialism? Undeniably, the Council is tasked to promote Britain, its way of life and its cultural heritage. If this can be counted as propaganda, there is clearly an attempt to curry a favourable view of this country. Why else would the Foreign Office foot £190 million of the Council’s £517 million annual bill? Why should the Government support such a large operation — a workforce of 7,300 spread around 109 countries?

The Council also concentrates its work not only where there is educational need but where its operations may do most to change perceptions: in the Middle East, across the Muslim world, in Africa and in former communist countries. Western culture may indeed prove alluring at the expense of local culture. But the Council resolutely denies this is its aim, and points to efforts to work with, not against, local traditions.

But when these clash, and when the Council runs up against censorship, political hostility and distortion, it makes few concessions. Before it was set up 75 years ago, all the talk was of using culture to counter the prevailing influence of fascism. That ideology has been defeated: but the British Council, like the BBC World Service, is still proving a potent weapon against totalitarian regimes around the world.

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