FRANCE was in a particularly dismal frame of mind last week. Nothing captured the mood as graphically as the scene outside the Société Générale bank headquarters where hundreds of employees gathered in drizzling rain on Thursday to voice worries that they were about to be laid off after a takeover bid.

“It is incredible that all this is the result of just one person,” said Sabine Delmas, a secretary standing beneath an umbrella. She was referring to Jérôme Kerviel, or “JK” as France’s celebrity rogue trader is widely known.

His trading had cost the country’s second-largest bank £3.7 billion, bringing one of France’s most revered financial institutions to its knees.

Strangely, however, it was capitalism that went on trial rather than Kerviel: he was on his way to celebrity status, a folk hero to many in France, where resentment of banks is deep-rooted and the relationship with the free market famously uneasy.

He may have been dismissed as a “terrorist” and “mutating virus” by his company but on the internet they were selling “Jérôme Kerviel is a hero” T-shirts and Ladbrokes was taking bets on who will play him in the flim. Some were even suggesting that he had saved the American economy from recession: according to that theory, the closing of Kerviel’s bad bets had accelerated a market slide that prompted a big cut in interest rates.

It was as if Nicolas Sarkozy, the French “hyper-president”, was handing Daniel Bouton, Société Générale’s chairman, a dagger with which to do the decent thing when he urged “highly paid” executives to take responsibility for the crisis: according to one opinion poll, 50% of the public saw the bank’s own missteps and mismanagement as being to blame. Only 13% thought Kerviel was at fault.

Nevertheless, as BNP and Crédit Agricole prepared to battle for control of the bank, Bouton, a respected pillar of the French establishment, clung to his job: a board meeting on Wednesday had brushed over the question of how the bank could have been so careless with its money; and how nobody noticed anything was amiss, even when a clearly distraught Kerviel, 31, was seen crying over his computer terminal several times in mid-January.

His distress was understandable: at one point he had been on the hook for €50 billion (£38 billion). He told police that superiors had “turned a blind eye” to his trading. That claim was dismissed last week by the bank.

However, an investigating magistrate threw out the most serious charge of attempted fraud: even though investigators found a magazine article entitled “How to Get Rich in 2008” in Kerviel’s flat, he had not made any personal gain.

Investigators have said that they want to quiz Bouton and other senior bank executives in the next few days as scepticism has grown at their attempts to cast the bank as an innocent victim of a “genius fraudster”.

As if he did not have enough on his plate, Bouton is one of dozens of defendants in a separate, money-laun-dering trial starting in Paris tomorrow. Revelations that he had earned €7m just in stock options last year have further fueled perceptions of the once-blessed bank and its leader as a symbol of capitalism’s worst excesses.

Even Sarkozy, supposedly a conservative who wants to deregulate the country’s rigid labour market and end the 35-hour week, put the boot into the free market last week as his approval ratings tumbled to 41%.

“Our financial system is walking on its head,” he said. “And it is losing sight of its goal, which is to lend money for economic activities that will ultimately generate profit . . . not to go and speculate on different activities which make massive fluctuations.”

Meanwhile, over the next few weeks, Société Générale employees are being asked to fill in questionnaires about the level of stress in their jobs, a long-planned project with a leading stress consultancy firm.

The survey seems long overdue: the company’s health and safety committee accused bosses last week of burying a report about the suicide of a trader who jumped off a footbridge after racking up a loss last June of €9m – pitiful, by Kerviel’s standard. In 2005 a man in risk control had jumped from the seventh floor. In 2006, an employee in back office operations jumped under a train.

“The pressure on bank workers has been growing over the past decade,” said Michel Marchet, a union representative at the bank. “The Kerviel crisis was bound to happen one day.”

Was stress – and pressure to make a profit – really what drove Kerviel into the folly of gambling with the bank’s billions? Or was he mentally unhinged, as a spokesman for the bank bluntly concluded last week?

Kerviel’s testimony to police after his arrest paints a much simpler picture. “Above all,” he told police, “I wanted to make money for my bank. That was my only motivation.” His first big profits came when he bet on the market falling shortly before the terrorist bombings in London in 2005. After the attacks the market fell – and he raked in €500,000.

By December 31, 2007, he had amassed a profit of €1.4 billion – far too much to declare to the bank without arousing suspicions.

But time was running out. E-mails began to arrive from the back office, questioning his colleagues about some of his trades. There had also been two queries about the volume of his trading from Eurex in Germany.

“They didn’t want to intervene,” he said of his colleagues. “It suited them that I was making money.”

A bank spokesman last week dismissed as “ludicrous” the idea that anyone else in the bank had been aware of Kerviel’s actions. “He’s saying those things in the hope of staying out of prison,” said the spokesman. “We could sue him for money that has been lost but, given the amount, it probably would not do us much good.”

It might be possible for the bank to claim his future earnings in compensation if he tries to profit with a film or a book, as now seems increasingly likely, given his celebrity status and growing support throughout France.

By the end of last week, the French communist party was comparing him with Alfred Dreyfus, the Jewish French army officer unfairly prosecuted at the end of the 19th century, and he was being hailed elsewhere as “Robin Hood” – a defender of the layman in the face of corporate giants – and a “Che Guevara of finance”.

In this outpouring of support was evidence of France’s unhappiness with its banks – and with capitalism in general. The socialist opposition is constantly calling for “clear legislation” to stop banks “getting rich off the back of the poor man”. The idea of money as shameful runs deep in France, where Sarkozy has come under attack for his “bling bling” lifestyle.

Given the poor state of French morale – a poll last week showed that “household confidence” was at its lowest in two decades – some analysts were predicting that the crisis at Société Générale could boost already significant opposition to Sarkozy’s market reforms.

In which case the unreformed French left will no doubt be calling for the canonisation of Kerviel.

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