Sam Younger, who became managing director of the World Service in November, is keen to stress that spreading the cosy Radio 4 ethos worldwide is not its main function. English is just one of 41 languages the service is broadcast in and accounts for only a quarter of total output.
"British expatriates are a small proportion of our audience," he explains. "Entertainment programmes are part of our commitment to reflect the range of life in Britain. If there was a squeeze, we may have to think about cutting them, but I don't think the World Service would be as successful if it didn't provide a range of programmes around a core of current affairs."
The purely political value of broadcasting for expatriates and travellers is confirmed every time the Foreign Office thinks about cutting its grant. As soon as the threat looms, the correspondence columns of the broadsheet papers are packed with pained letters from the tribe of the great and good, who sing the praises of the World Service and aver they could not leave home without it.
Rather fewer letters come from fans of the news read in Uzbek, one of the eastern European languages Younger added last month to his portfolio. Yet it is in the burgeoning local language broadcasts, increasingly on FM as well as short wave, that he thinks the service makes its greatest contribution.
"The former Soviet Union is a priority area for us and the Foreign Office," he says. "It isn't adequate to think you can go on making the impact you want there just by broadcasting in Russian. We're getting more sensitive to the way nations are developing."
The word "impact" crops up time and again as he describes what the World Service is trying to do. If you judge impact by numbers, it is a success, with a confirmed weekly audience of 130 million, plus uncounted millions in places such as China, Burma andIran. Younger's programmes reach more people than the three next biggest broadcasters combined.
What is unclear is precisely what this impact seeks to achieve. John Birt, the director-general, put the question a few months after he joined the BBC as deputy D-G in 1987. At a top-level staff conference, he asked John Tusa, then managing director of the World Service: "What audience are you aiming at? What cultural assumptions are you making?"
A third and tougher question is this: what exactly, in the post-colonial and post-Cold War age, is the message Britain has to deliver? When the service was launched in 1932, there was no ambiguity about the answer. In those days, it was called the EmpireService, handing down the word from London to scattered overseas possessions, celebrating British achievements and promoting foreign policy objectives.
Today, it pursues a different path, with a deserved reputation for impartial news and comment. As in cricket, we remain the world's best umpires, although we are no longer very good at the actual game.
Younger is proud of this switch of emphasis. "The Foreign Office recognises that what credits Britain lies in the BBC's editorial and programme-making independence," he says. "A country with the confidence to reflect warts and all what it and the world is about has a higher credibility than an organisation putting out propaganda."
So devoted is the World Service to even-handedness that it has sometimes been accused of giving too little support to British troops overseas, such as in the Suez in 1956 and the Falklands in 1982. As head of the Arabic service during the Gulf War, Younger was involved in such an issue when criticised by Saudi Arabia and Kuwait - both British allies.
"They felt a broadcasting organisation coming from Britain should reflect alliance viewpoints and not give Saddam a platform," he recalls. "The Foreign Office said we needed to be very sure we were balanced but there was never a direct attempt to ask us to move away from our normal journalistic principles.
"That's not to deny there are times when what the BBC broadcasts makes things awkward in the short term for the Government. They would say mostly that the long-term benefit of keeping the BBC independent outweighs short-term irritation."
Younger, 42, had been head of the Arabic service for a year when the war broke out. Reluctant to accept the job, a notorious political minefield, he was persuaded it would be a good career move. He did the Gulf balancing act so adeptly that promotion didfollow.
His swift rise has come as something of a surprise to people within the service who remember him in the 1970s as a donnish, diffident young journalist specialising in Middle East affairs. Some felt he lacked the gravitas of his father, Sir Kenneth Younger, a former Labour minister and director of Chatham House, the prestigious foreign affairs institute.
Yet he has matured, and the appointment of an experienced insider to the top job has been broadly welcomed by staff at Bush House, London headquarters of the World Service. They resented John Tusa's replacement with Bob Phillis, who came to the BBC from commercial television.
To ice Younger's cake, it was recently announced that the Foreign Office would allow the service to decide for itself which languages to broadcast in and for how many hours. Yet, as Younger admits: "If they were terribly keen that we broadcast in, say, Japanese and insisted we do it, we would."
So the World Service is not an independent broadcaster, however much it may sound like one. Indeed, Younger and his staff of 2,500 find themselves squeezed uncomfortably by two masters. During his year in charge, Phillis tightened the bonds with BBC headquarters, a mile away at Broadcasting House.
Instead of having its own free-standing directorate, the World Service has lost a measure of sovereignty by becoming part of BBC Worldwide, a holding company chaired by Phillis which includes the commercially funded World Service Television, which draws (for a fee) on Bush House resources.
Of his twin controllers, Younger has more to fear from the Foreign Office. The grant, reviewed every three years, is declining in real terms. If he were to cut back on broadcasting in English, he would risk alienating the armchair warriors who lobby so assiduously for him on the letters pages.
The danger to the World Service is that politicians may wonder whether it's the best because no other country sees much point in making the investment. They may steel themselves to ask what interest is served in being the world's most impartial broadcaster. What if they should find no convincing answer?