THE victims of Soviet communism would find it hard to understand, but a giant yellow banner was unfurled in the centre of Paris last week, bearing portraits of Lenin and Stalin. “Only socialism can save the world” it proclaimed in black ink.

Welcome to the annual May Day rally in Paris, always a festive affair. Salsa music blared from the back of a lorry and an aroma of barbecued Merguez sausages filled the air. Trotskyite militants handed out leaflets denouncing the capitalist system.

The march, which attracted 60,000 people under flags emblazoned with the hammer and sickle, was a reminder of how different France is to other European countries with its lingering affection for ideas jettisoned long ago elsewhere in the world.

It was also a warning to Nicolas Sarkozy, the reform-minded conservative candidate for the presidency, of the trouble that may lie in wait for him if he wins the presidential election today and embarks on ambitious plans for modernising a country badly in need of renewal and disillusioned with its ruling elite.

President Charles de Gaulle once famously remarked that it was impossible to govern a country with so many different cheeses. Over the past few years the truth of that tenet has been confirmed as the government of outgoing President Jacques Chirac has limped impotently from one crisis to another.

Is Sarkozy any more likely to succeed than his discredited predecessors?

He would like to make the notoriously grumpy French feel better about themselves in the epoch of globalisation, raising wages and productivity, reducing unemployment and restoring a sense of pride in la belle France and her history.

Seldom has an election generated so much excitement or expectation of change: turnout in the first round of voting on April 22 was at its highest since 1974 and Sarkozy’s clash with Ségolène Royal, his Socialist rival, last Wednesday night was watched by more than 20m people, almost as many as followed the country’s fortunes against Germany in the World Cup final of 2006.

Sarkozy, 52, and Royal, 53, are much younger than previous incumbents. Royal is the first woman to have come this close to the presidency and Sarkozy the first presidential finalist whose father was not French – he fled communist Hungary for Paris after the second world war.

Sarkozy, ahead in all 27 polls taken since he won the first round, knows how heavy a burden rests on his shoulders. He has announced that if he wins, he will go on a retreat for a few days to prepare himself, like a boxer ahead of the big fight, for the challenge of running the world’s fifth largest economy.

“I will need to be alone with myself,” he said.

Royal, a charismatic mother of four, fought tooth and nail to convince her countrymen not to back “Sarko”, as they referred to the combative former interior minister. Her last-minute appeals to voters, however, took on an almost desperate air as she sensed the electoral arithmetic turning against her.

On Friday morning she warned that France could slide into violence if Sarkozy, a famously divisive figure, won the election. She said she was “issuing an alert” that his victory could “trigger violence and brutality across the country. His candidacy is dangerous. That is why I am asking voters to think twice”.

Sarkozy’s increasingly confident team called such attacks “outrageous” but nobody disputed the possibility of a toxic brew of antiSarkozy grievances erupting in violence, particularly in the immigrant suburbs, if his victory is announced tonight.

Arab and African residents of the banlieues, as the suburbs are known, have been in an angry, vengeful mood since Sarkozy described young delinquents as “scum” and “thugs” in 2005.

His comments were widely believed to have contributed to the most severe violence in France in four decades, when 10,000 cars were burnt in a rampage of rioting.

The grim housing estates ringing most big French cities were buzzing last week with rumours of another “explosion” of anger if Sarkozy wins.

The banlieues were not the only potential flashpoint, however. A different group of “thugs” could prove to be just as troublesome for a Sarkozy presidency.

One of Sarkozy’s first priorities was to introduce a law by July to curb the power of organised labour. The unions responded by turning their May Day parade last week into a giant protest against “Sarko”.

Militants handed out “stop Sarko” badges and stickers. Some of the leaflets on offer depicted him as a vampire.

The “TSS”, or “tout sauf Sarkozy” – “anyone but Sarkozy”, campaign has featured video clips attempting to link him with everything from racism to the Church of Scientology. One of them featured Sarkozy’s mother describing the “privileged” background he came from in the affluent suburb of Neuilly. It seemed to undermine his claims that he had been forced to work as an ice-cream seller to help to finance his studies.

One of the protesters hoisted aloft a placard that said “Sarkozy = Napoleon”. Another marcher shouted into a loud-speaker, “Arrest Sarkozy, free the sans papiers” – a reference to those without documents who face expulsion following Sarkozy’s crackdown on illegal immigrants when he was interior minister.

Another performer in this antiSarkozy circus was a man on a lorry dressed in a black cape and helmet who was trying to depict Sarkozy as Darth Vader, the “dark force” of the Star Wars films.

At the front of the parade was Bernard Thibault, leader of the CGT, France’s most powerful union. “He should think twice about doing anything without negotiating with us,” he said. “If not, there will be reactions. Strong reactions.”

In a cream linen jacket, the chain-smoking Thibault was flanked by muscle-bound heavies clutching their CGT banner. One said the march was “a show of strength to remind Sarko to get ready for the third round of the election that will be fought on the street”.

Various governments have tried over the past 12 years to implement laws to free a stagnating economy, each time backing down after noisy street protests, some of them led by Thibault and his followers from the placard-wielding far left.

That is what happened in 1997, forcing a timid Chirac to give in, and again last year, when the government proposed a law that would have made it easier for employers to sack workers. The idea was to encourage hiring but it provoked a wave of protests that forced the government to retreat.

Only about 8% of French workers belong to trade unions but they have a powerful grip on public services and some important companies, making it easy for them to paralyse the country by blocking transport systems.

By passing a law to ensure minimum public services during a strike, as well as secret ballots for union members, Sarkozy hoped to draw the teeth from the unrest that he knows will follow what, by French standards, is his extremely ambitious package of reform. It would in effect end the 35-hour week and other “social perks” that union militants consider to be sacrosanct. Railway workers, for example, can retire at 55, the shortfall in their pension contributions being made up by taxpayers.

Not only does Sarkozy want to change that. His call last week to “liquidate” the May ’68 culture of protest – the very culture that allows Thibault and friends to settle political differences on the street – was another example of what union bosses called a “Thatcher-style” effort to castrate them and sell their country into free-market slavery.

“Everybody must know,” said Bruno Juilliard, head of the UNEF student union, “that the unions will mobilise to defend their rights if they are under threat.”

Sarkozy, however, seemed to be spoiling for a fight. “I’m sorry if M Thibault does not like it, but it’s the French who choose,” he said.

To his fans it makes him a hero: only this pugnacious, stubborn and hyperactive personality with a determination to succeed is capable, they say, of dragging France out of its malaise and reconciling it with the free market.

His enemies, however, echo Royal’s view of him as a dictator figure whose abrasive style would deepen the French fracture. Perhaps the most serious insult that she has hurled at him in this antiAmerican country is the charge that he “imitates” President George W Bush. “He has the same neoconservative ideology,” she said on Friday.

Sarkozy has tried to tone down his aggressive image. In his final campaign rally in Montpellier on Thursday night, he struck a more compassionate tone to challenge what had been Royal’s monopoly of the heart.

He invited voters to join a “fraternal” republic in which there was a place for “even the most humble, the most fragile, the most wounded by life, the most dependent”.

He spoke of the tragedies of Alzheimer’s disease and depression, the plight of single women bringing up children, the difficulties of being, like him, an immigrant’s son or of living in a neglected suburb. He spoke of the need for “fraternity and respect” and said that he wanted to defend his convictions “without hatred, scorn, arrogance or violence”.

At the same time he emphasised that he had meant what he said about troublemakers in the suburbs. “I used the word scum,” he said, adding: “People have reproached me for it, but I regret nothing.” The crowd erupted in applause. “What sort of educators would we be if thugs cannot even be called thugs?”

He continued: “They tell me that I should not create tension, that I should not give a pretext to the wreckers, that I must at all cost avoid creating conditions for confrontation. Does that mean that the police must hide? Shut their eyes? Leave the thugs free to act?”

There were chants of “no” from the crowd. He went on: “People accuse me of encouraging public anger. But who’s angry – the yobs? The drug traffickers? I can assure you: I do not seek to be the friend of yobs. My aim is not to make myself popular among the traffickers and the fraudsters.”

In his presidential campaign Sarkozy was sensible, perhaps, not to set foot in the suburbs.

“People despise him so much that one of these days I wouldn’t be surprised if someone tried to whack him,” said Abdel Benarbia, a 15-year-old schoolboy sunning himself on a patch of grass in the shadow of his tower block in Clichy-sous-Bois, a suburb 10 miles from the centre of Paris where the 2005 riots began.

Kader, his elder brother, agreed and repeated what sounded more like a promise than a prediction: “If Sarko gets in, it’s going to explode.” Not that they wanted to play any role in the violence.

Far from it. They were afraid of what might follow. Already routine police checks are a constant anxiety for the Algerian-born Kader, who has a job loading meals at Charles de Gaulle airport and wants to keep it. He was worried that “oppression and racism” would only get worse under Sarkozy.

“If they accuse you of something round here, it’s their word against yours,” he explained. “It’s easy for the innocent to get caught up in trouble.”

There may be hope for the banlieues, however. In these urban badlands of high unemployment, crime and hopelessness, the television satellite dishes may be tuned to Morocco but participation in French political life is increasing.

“We’ve been telling people that unless they register to vote no politician will ever give a damn about them,” said Samir Mihi, a personal fitness trainer who is running a voter registration campaign in Clichy-sous-Bois. “We want people to use the ballot box, not boxes of Molotov cocktails.”

Sarkozy can feel happy about that. Yet it will be some time before the “fraternal republic” exists anywhere other than in his imagination.

For election results and analysis, including Charles Bremner’s Paris blog.

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