Belgium has launched a drive to reshape its institutions, following months of government paralysis. At the heart of the crisis is a tension between the Dutch-speaking Flemish and Francophones. In the final of a series of articles, Henri Astier asks if Belgium can remain united, and considers the lessons for other multi-ethnic entities.
Earlier this month the Flemish sports minister suggested restructuring Belgium's football federation, creating Francophone and Dutch-speaking wings.
The plan drew loud boos from French-speakers.
The vice-president of national champions Standard Liege called it as a "dangerous first step towards a split" - and threatened to make an even bigger step by joining the French league if it went ahead.
The row neatly encapsulates what some fear could be the unravelling of Belgium itself.
The events might unfold along the following lines: the autonomy-minded Flemish, who are richer and more numerous than French-speakers, grow impatient with protracted devolution talks; in next year's regional election Flemish nationalists do well; alarmed Francophones seek solace in a union with France.
A recent poll by Le Soir newspaper suggested that 49% of people in Wallonia, the French-speaking half of Belgium, want to become French if their country breaks up.
"There is a vicious circle where Francophones feel that radicalisation is gathering pace in Flanders," says Olivier Mouton, Le Soir's political editor.
"They brace themselves for Flemish independence and become radicalised themselves."
The paradox is that separation would happen without either side actively seeking it.
Only about 10% of Flemish voters want independence. Support for unity is overwhelming in Wallonia.
Could Belgians really be sleepwalking towards separation? Flemish leaders say they only want to reform the Belgian state, not dismantle it.
"I am not in favour of the independence," Kris Peeters, Flanders' Minister-President, told the BBC News website. "Solidarity" between Flanders and other regions will remain, he insists.
However his stated goal is a "Copernican revolution" where federal powers are greatly reduced and the main decisions taken by regions.
"For me the most important level will be the regional level," he says.
Mr Peeters' career reflects this belief in the regions' supremacy. He spurned a seat in the Belgian parliament.
Asked what he would do if offered a key federal ministry he says unhesitatingly: "I would turn it down too."
And his description of the current "dialogue between the communities" points to his ideal of quasi-sovereign entities: "We have two delegations, like two separate states discussing a treaty."
Some commentators believe that the dynamic of Belgian politics lead the French and Dutch speakers away from each other.
Following devolution reforms over the past 45 years, all parties are now either Dutch-speaking or French-speaking.
Gie Goris, editor of Mo magazine, notes that countries which accept ethnically based politics, like Sri Lanka, are inherently unstable.
Belgians are not about to kill each, Mr Goris admits, but they should be wary of ever more devolution: "The changes you bring to the political build-up of a country have a long-term snowballing effect."
Belgium has no common public sphere to speak of. The communities don't watch the same TV channels.
Celebrities from one side can walk totally anonymously across the "linguistic border" - as it is tellingly called. "You have a whole different cultural universe in the north and the south of the country," says Yves Desmet, political commentator for the Dutch-language De Morgen newspaper.
Differences are striking in both big and small ways.
Although the railways are federal, train tickets are not bilingual - in Flanders they are in Dutch only, while tickets for the same journeys printed in Wallonia are in French.
Health habits also vary widely.
French-speakers, like most southern Europeans, are heavy users of antibiotics and expensive diagnostic procedures such as MRI scans, while the Flemish tend to frown on these, as do most northern Europeans.
To be sure, some things still unite Belgians. They drink the same beers. They all cheered the mixed team that won silver for Belgium in the women's 4x100m Olympic relay in Beijing.
The king commands respect on both sides - although his Flemish subjects are more lukewarm in their affection.
In economic matters, the picture is mixed. Flanders and Wallonia are each other's main trading partner, but in the booming technology sector contact is limited.
Nonillion, an up-and-coming IT firm based in Ghent, does not have a single customer in Wallonia.
Chief executive Rudi Van den Bossche says French is not a requirement for his staff. "Most of our customers ask for bilingual - meaning Dutch and English," he says.
In Brussels, on the other hand, bilingualism tends increasingly to be the norm. Still, the overall picture is one of division.
"If you were a Martian and read the Flemish newspapers and the Walloon newspapers you would think they're describing two different countries," says De Morgen's Yves Desmet.
You say you want a revolution
But does this continued estrangement mean that Belgium is doomed? Many commentators do not think so.
First there is the question of Brussels. The capital is a region in its own right, distinct from both Flanders and Wallonia. It is also richer than both, as well as the seat of the EU and Nato.
As a result, neither side can accept a takeover of the other on Brussels. And without it, each is a marginalised hinterland. The status quo is thus the best option for both.
Moreover, Belgium's proportional representation voting system is a big hurdle for those seeking radical change.
In a first-past-the-post systems, a winner clearly takes charge. But Belgian leaders have to cobble coalitions with groups from both sides of the divide.
"When [President Nicolas] Sarkozy is elected in France, he can implement a policy of 'rupture'. But with us, rupture is never possible because compromise must always be reached with other parties," says Belgian deputy Foreign Minister Olivier Chastel.
Revolutions, Copernican or otherwise, are mightily difficult to bring about in Belgium.
According to Dave Sinardet, a political scientist at Antwerp University, the fact that Belgium's communities lead largely separate lives, and have no great affection for each other, need not spell the end of the country.
"These things are also true of the European Union and are not a problem for its continued existence," he says.
This raises an interesting point about parallels between Belgium and the EU.
The country was long regarded as a model for nations living in harmony under common institutions.
Then, over the past year, the Belgian stalemate was seen as a reflection of the EU's divisions and the travails of its reform treaty.
The real parallel, however, may be neither rosy nor gloomy, but bitter-sweet.
In both Belgium and the EU, shared institutions seem able to muddle through despite indifference from their constituent nations - rather like old couples who don't talk but stay together because separation is more trouble than it is worth.
Federalists both in Belgium and Europe might see this as too negative an argument for union - but it is a comfort of sorts.