Back in December 2006, a group of Belgian TV makers interrupted a programme about the future of the country to announce that the parliament in the Dutch-speaking part of the country, Flanders, had declared independence from the rest of Belgium.

Like all the best hoaxes, people were fooled because the scenario was just about credible. Today, even the over-the-top scenes the TV makers conjured look prescient: a Brussels tram blocked as it tried to enter the new Flanders; King Albert II deposed. Although King Albert is unlikely to feel the need to flee – this isn't 18th-century Paris – the monarch seems to hold the fate of a country in his hands. Instead of the usual duties of a 21st century democratic monarch of rubber-stamping parliamentary laws, the king must decide whether to accept the resignation of Prime Minister Yves Leterme and what to do about the Leterme's declaration that the 6.5 million Dutch-speaking Flemish people, the 4 million French-speaking Walloons and the smaller German-speaking community have "conflicting visions of how to give a new equilibrium to [the] state".

What real chance does the king have of avoiding a split between the Walloons and the Flemish, given that, after hours of talks with leaders from all of the country's main political parties, the positions of Flemish and Walloon politicians are as entrenched as ever? They are still divided on whether to devolve more power to the regional parliaments and on the voting rights of French-speakers in a Flemish-dominated area on the outskirts of Brussels.

Even if the king turns to a new, more charismatic prime minister as a peace-broker, his prospects look gloomy when you consider Leterme's five-party coalition government only assembled after a nine-month deadlock following the failure to form a government after the elections of June 2007.

What amazed me during that crisis was how nonchalant some Belgians seemed to be when I asked how it felt to be on a rudderless ship, or how worried they were about the future of the country. One French-speaking friend (who, like most university-educated Belgians, also speaks the other community's mother tongue) even told me the country was running fine, thank you, without a government, proving ordinary people could get along without meddling politicians.

This week, I can't help but compare his indifference to the denial of a partner in a troubled marriage. However, if some Belgians are in denial, others are perhaps too easily seduced by a quick divorce. Splitting up Belgium, if it happens, will probably involve a bitter settlement – one which will have to separate intermeshed economies, share out the national debt and decide the status of Brussels, which has a French-speaking majority at the heart of the Flemish region.

Such a process would inevitably take the shine off Belgium's hosting of the European Union institutions. As former Belgian prime minister Wilfried Martens put it: "We are the centre of the European Union. How could we give such a bad example to all the member states if we were to split?"

For other Europeans, more important than Belgium's loss of legitimacy to be at the heart of Europe may be the dilemma of whether any of its breakaway nations can lay claim to be European Union members. Catalan and Scottish nationalists are already lobbying in Brussels alongside Flemish separatists, insisting they are rightful existing EU members even if they form new countries.

Some say the matter is one for European constitutional lawyers. My view is that the question may also be one for European voters. The idea of an independent Flanders used to be only seriously defended by the region's far right, racist party Vlaams Belang, which means "Flemish interests" in Dutch. If the ideas of that party eventually influence the foundation of any new nation state, its laws and institutions, such a country has no place in the EU.