Just when you think you know what the French are going to do, they defy your predictions. Who would have imagined a few months ago that Paris would be the second largest contributor to NATO's war on Yugoslavia, after the US and ahead of Britain? That the French President and Prime Minister - from opposite sides of the political spectrum - would show complete unity in their condemnation of Slobodan Milosevic and support for NATO policies? That two-thirds of the French public would approve of the air campaign, not even flinching at its blunders?
There was little in the past 33 years to indicate France might prove such a stalwart ally in the Balkans. General de Gaulle infuriated Washington by kicking NATO out of Paris and withdrawing from its integrated command back in 1966.
Francois Mitterrand had an acute sense of historical loyalty to Serbia, going back to the Franco-Serb alliance in the first World War, and he swore that as long as he was president, France would never bomb Belgrade.
Two years ago, the prosecutor at the International Court of Justice in The Hague accused French forces of protecting Bosnian Serb war criminals; two French army officers lost their jobs after spying for Serbia. France criticised US and British air strikes against Iraq, and President Jacques Chirac abandoned plans to return to NATO's integrated command because Washington refused to give more power to Europeans.
Yet France's surprising stand in Yugoslavia owes much to the personality of Mr Chirac, who served as a lieutenant in the war in Algeria. He was enraged when Bosnian Serbs took French UN peacekeepers hostage four years ago. "For Chirac it was inconceivable that a soldier not be allowed to fire back when he is shot at," Herve Algalarrondo of the weekly Nouvel Observateur recalls. "Chirac is interested in all things military. In 1995 he installed a 3-D map of the Bosnian war zone next to his office at the Elysee and spent hours studying it with his officers, discussing the location of tanks and artillery pieces."
Although his RPR party proclaims itself Gaullist, Mr Chirac is not typical of the French right. Having worked and studied in the US as a young man, he does not feel the visceral anti-Americanism of many French politicians. Nor does he share the right's objection to intervention in sovereign nations. Like the Socialist prime minister, Lionel Jospin, Mr Chirac has a strong idealistic streak. Both men have taken a moral stance in Yugoslavia, saying they will not allow disputes in Europe to be solved by murder and ethnic cleansing. There is something of the old mission civilisatrice about France's determination to end what it sees as medieval behaviour on the eve of the 21st century.
Buoyed up by their war performance, Mr Chirac and Mr Jospin are enjoying record popularity ratings of up to 70 per cent in opinion polls. To the annoyance of Washington, Paris keeps pushing for a UN Security Council resolution to confer legitimacy on the war and the French have also insisted on an important diplomatic role for Russia.
Paris was delighted when Tony Blair signed a joint Franco-British declaration on European defence at St Malo last December. "The Elysee considers it the most important European achievement after the single currency," says Pierre Haski of Lib- eration. "They don't want the thread to be broken. For European defence to be credible - for it to go ahead - France had to participate [in the war on Yugoslavia]. France's primary objective in this is to advance European defence."
French officials often lament that most EU members would be happy to leave defence policy to NATO. It is, Foreign Minister Hubert Vedrine has said, the equivalent of the Europeans adopting the dollar as their common currency instead of creating the Euro. France will assume the EU presidency in the second half of 2000, and Paris wants to establish a genuine European defence identity by the end of its mandate. Mr Chirac has also proposed that the UN appoint the EU as provisional administrator of Kosovo once a settlement is reached.
At the beginning of the Yugoslav war, Mr Chirac privately opposed the US's "zero-risk" high-altitude bombing strategy. He was expected to push for ground troops at the NATO summit in Washington at the end of April but did not do so - perhaps because France would find it difficult to muster a division of professional soldiers to send to the Balkans. Despite a quickly corrected gaffe by Prime Minister Jospin in which he appeared to advocate the deployment of ground troops, France's official position is that a ground offensive is not under consideration and would require both a UN Security Council resolution and a vote by the French National Assembly.
The plight of the ethnic Albanian refugees galvanised French public opinion in favour of the war. Opposition comes mainly from the extreme left and right, out of anti-Americanism and sympathy for Mr Milosevic. Only a handful of politicians and newspaper columnists have opposed it on the more rational grounds that the all-air strategy is disastrous. "French people are very ideological," explains Mr Algalarrondo. "In France, you must be for or against something. We don't like lukewarm solutions."
"Cohabitation" between a right-wing president and a Socialist prime minister has also unified the French in favour of the war. The Gaullist RPR is represented by Mr Chirac, while Communists, Greens and Socialists are all present in Mr Jospin's government.
Despite a venomous debate between pro- and anti-war French intellectuals, there is no question in official circles of tempering French support for the war.
The French chief of staff, Gen Jean-Pierre Kelche, was in Albania last weekend, sounding like US general Wesley Clark when he vowed that "Milosevic will back down before NATO does".
French resolve has stunned the Serbs as much as it has Washington. "In the first World War, we had mixed battalions with the Serbs," a desk officer in the Foreign Ministry sighed nostalgically. "We were pro-Serb; now we're anti-Serb," one of her colleagues shrugged. Serbs see this transformation as a cruel betrayal.
A few weeks ago in Belgrade, outside the vandalised French cultural centre in Kneza Mihailova Street, it seemed deeply ironic to find a young woman selling postcards of the first World War. The reproductions show Serb women hurling flowers on the French soldiers who came to liberate them. Other captions describe the Serbs as "a heroic people". France's long friendship with Serbia now looks as quaint and outdated as the old hand-coloured lithos.