They gaze, alarmed, at their neighbours – Greece, Italy, Ireland, Spain and Portugal – and wonder if the euro and the entire EU are about to sink under the weight of all that debt. But then they look closer to home, at their own country and Germany – the bi-nation kernel of Europe and its economic engine – and another, much older problem rears its head The French realise it's crossroads time for the euro. There must be a new start to restore growth and confidence, eradicate fraud and establish fiscal rigour and structural reforms. But shock treatment and recession, even rupture and secession from the eurozone, are less on their minds than a Europe inching backwards, towards its ancient national divisions – the same frontiers that brought them at least two world wars.

One newspaper columnist here has noted that Europe explodes with regularity at the opening of each new century. Bonaparte blew it up at the beginning of the 19th. At the start of the 20th, it was the First World War. Though it's a monetary, not a military threat this time, and the continent's currency, not its concord, is under siege, some worry that a spark such as Greece could, like Sarajevo in 1914, trigger a far greater calamity.

Germany's chancellor, Angela Merkel, is seen in certain quarters as the traditional Teutonic Teufel that has tormented France throughout the ages, but in a new form. A robust German economy is allowing her to throw her weight around this time. The French fear a 'Merkozy Pact' that would wed German austerity to French solidarity; a flush Germany will fork over cash if France hands over some of its sovereignty.

President Sarkozy wants to get his people to accept some loss of autonomy which will benefit Europe as a whole. But this is anathema to a nation fanatical about remaining mistress of her own destiny. Their British cousins use the same argument against joining Euroland.

France's left wing not only believe a Franco-German compromise can't last, but see it as capitulation and evoke 1938, likening Sarkozy to Edouard Daladier at Munich. Others accuse the chancellor of "Bismarck politics"and warn against a "resurgence of German nationalism". Such outbursts prompted the French prime minister, François Fillon, among others, to denounce"old demons of Germanophobia".

The French are not prepared to save the euro if it means losing their independence and will accept no German diktat. In this season of populist waves, another could rise on French soil to protect what are considered Gallic values against the invasion of the German model.

Henry Kissinger once famously complained about the splintered Old World."If I wanted to phone Europe,"he asked,"whom would I call?"The French will not be amused if the continent's number becomes a direct line to Berlin.