IN RECENT years Brussels has been a fine place to observe the irresistible rise of English as Europe's lingua franca. For native speakers of English who are lazy about learning languages (yes, they exist), Brussels has become an embarrassingly easy place to work or visit. English is increasingly audible and visible in this scruffily charming Belgian city, and frankly rampant in the concrete-and-glass European quarter. Now, however, signs of a backlash are building. This is not based on sentiment, but on chewy points of economic efficiency and political fairness. And in a neat coincidence, Brussels is again a good place to watch the backlash develop.

Start in the European district, where to the sound of much grinding of French and German teeth, the expansion of the European Union has left English not just edging ahead of the two other working languages, but in a position of utter dominance. The union now boasts 27 members and 23 official languages, but the result has been the opposite of a new tower of Babel. Only grand meetings boast interpreters. At lower levels, it turns out, when you put officials from Berlin, Bratislava, Bucharest and Budapest in the same room, English is by far the easiest option.

Is this good for Europe? It feels efficient, but being a native English-speaker also seems to many to confer an unfair advantage. It is far easier to argue a point in your mother tongue. It is also hard work for even the best non-native speakers to understand other non-native versions of English, whereas it is no great strain for the British or Irish to decipher the various accents.

François Grin, a Swiss economist, argues that Britain enjoys hidden transfers from its neighbours worth billions of euros a year, thanks to the English language. He offers several reasons, starting with spending in Britain on language teaching in schools, which is proportionately lower than in France or Switzerland, say. To add insult to injury, Britain profits from teaching English to foreigners. “Elevating one language to a position of dominance is tantamount to giving a huge handout to the country or countries that use it as a native language,” he insists.

What about the Europe outside the bubble of EU politics? Surely the rise of English as a universal second language is good for business? Perhaps, but even here a backlash is starting, led by linguists with close ties to European institutions and governments. They argue that the rush to learn English can sometimes hurt business by making it harder to find any staff who are willing to master less glamorous European languages.

English is all very well for globe-spanning deals, suggests Hugo Baetens Beardsmore, a Belgian academic and adviser on language policy to the European Commission. But across much of the continent, firms do the bulk of their business with their neighbours. Dutch firms need delivery drivers who can speak German to customers, and vice versa. Belgium itself is a country divided between people who speak Dutch (Flemish) and French. A local plumber needs both to find the cheapest suppliers, or to land jobs in nearby France and the Netherlands.

“English, in effect, blocks the learning of other languages,” claims Mr Baetens Beardsmore. Just as the global rise of English makes life easy for idle Britons or Americans, it breeds complacency among those with English as their second language. “People say, ‘well, I speak English and I have no need to learn another language.'” He cites research by the European Commission suggesting that this risk can be avoided if school pupils are taught English as a third tongue after something else.

A huge government-financed survey of Brussels businesses reveals a dire shortage of candidates who can speak the right local languages (40% of firms have reported losing contracts because of a lack of languages). One result is a very odd labour market. By day, Brussels is more or less bilingual, hosting a third of a million Dutch- and French-speaking commuters from the prim suburbs, who fill the lion's share of well-paid graduate jobs. Once night falls, Dutch-speakers are in a small minority.

Not getting on their bikes

Moreover, among permanent Brussels residents, unemployment hovers around 20%. Just a short journey away, in Dutch-speaking suburbs such as Zaventem (home to the airport), unemployment is 4-5% and employers complain of worsening labour shortages. Even within Brussels, thousands of job vacancies go unfilled every month because nine in ten jobseekers cannot read and write in French and Dutch, prompting employers to bin their applications.

Olivier Willocx of the Brussels Chamber of Commerce and Industry argues that too many Brussels natives are “allergic to learning Dutch”. The rise of Dutch is painful for some. French was once the language of the Belgian and Brussels elite, but the post-war period has seen Dutch-speaking Flanders (as the north of Belgium is known) boom. “Like it or not, the real economic power in Brussels is Flemish,” contends Mr Willocx.

Hardline nationalist politicians in Flanders must take some blame because they have done a lot to make French-speakers feel unwelcome. The head of the Brussels employment service, Eddy Courthéoux, also questions the sheer number of job advertisements that demand both Dutch and French, saying that for some “it is just a way of avoiding hiring a foreigner”: code for Moroccan, Turkish or African immigrants.

Perhaps Brussels should accept its fate as an international city, and switch to English, like some European Singapore (although with waffles, frites and dirty streets)? For all his problems finding jobs for monolingual locals, Mr Courthéoux looks appalled. “Living in a bilingual city is not a misfortune, it makes life rich and interesting,” he argues. Some would call this pure sentiment, others might suggest that it reflects hard-nosed economics. But Brussels is actually a good place in which to hear the point and simply nod your head.