I love France. I even like the French – which is an unusual combination for the British. I find it a frustrating place, not least because of the mystery of why the country which produces the finest cheese on the planet invariably refuses to serve it with biscuits.

Such obstinate eccentricity is, I suppose, an indispensable aspect of its collective personality. In the modern world, nonetheless, character alone is not enough to ensure the success of a society. A strong France is not only in its own interests but that of Britain, Europe and the wider world. Which is why so many of France’s friends abroad will welcome the election of Nicolas Sarkozy as the President.

None of this is said out of Anglo-Saxon superiority. There is more than one way for a country to adapt to the challenges of globalisation. It is arrogant to declare otherwise. The tragedy of France, however, is that its elites (with the exception of Mr Sarkozy) have spent 20 years or so not debating how to reform while preserving the unique assets of France, but crying foul about having to make such a move, or even dodging the issue entirely. If Ségolène Royal had won last night she would have had a mandate to continue that behaviour. It would have been immobilism reaffirmed – the status quo with lipstick.

Yet in many ways France should have been the country where the political class could have imposed most quickly the disciplines demanded by a changed world. In theory it has had, for almost 50 years, a regime that appeared to enable leaders to act decisively.

This had not been achieved effortlessly. For centuries the instincts of France when times were tough was to “blame the system”. Between 1789 and 1958 the country experienced no fewer than 17 different forms of constitutional order. The rules of the game alternated between the Left (which favoured a strong parliament and a weak executive) and the Right (which invariably supported the opposite combination). The instability was such that there was a widespread joke about a man entering a bookshop and asking for a copy of the constitution only to be informed that “we don’t stock periodicals”. Volatility was the order of the day (periodic invasion by the Germans did not help, either).

The Fifth Republic, the creature of Charles de Gaulle, was designed to put an end to that. It ensured consensus by the brilliant innovation of a directly elected President alongside a National Assembly which, if astute, he could dominate. It was an outcome that could be presented as a compromise between the Left and Right but largely on the terms of the latter. It was no coincidence that France’s extraordinary economic boom during the 1960s occurred only after it had acquired a political structure that allowed it to avoid the anarchy of the past.

The blunt truth about the past two decades is that De Gaulle’s masterpiece is mouldering. Only two men have been President since 1981 (François Mitterrand and Jacques Chirac) but in that time there have been no fewer than 11 prime ministers, with another one coming along shortly (a rate of attrition to compete even with Italy). Finance ministers and foreign ministers have been similarly fleeting. No French Government has been reelected since 1978, with six straight defeats for the incumbents. Both Mitterrand and Chirac endured periods of “cohabitation” when their opponents controlled the legislature, rendering them little more than democratic monarchs. It is no wonder that hard choices have been avoided.

The most lamentable aspect about the manifestly miserable Chirac tenure is that in the past five years he has controlled everything in the manner that De Gaulle envisaged the head of state should – and he has done nothing with the resources at his disposal. On the night in 2002 that he crushed Jean Marie Le Pen and his right-wing National Front by 82 to 18 per cent I wrote a piece on these pages headlined “Chirac wins big, but it will mean so very little”. “Very little” turned out to be an overestimate of Mr Chirac’s achievements.

Which is why Mr Sarkozy matters so much at this moment. His victory will be followed swiftly by a parliamentary ballot that should break the taboo of almost 30 years and permit the centre-right majority in that place to be returned to office. In the aftermath of Ms Royal’s defeat the Socialist Party will return to what it does best, tearing itself to bits. The slogan Liberté, Egalité, Fraternité was plainly coined by the French Left out of irony.

The new President will soon have the tools that De Gaulle wished for him. Which means that, if he does not succeed, more then his reputation will be damaged. “Blame the system” will once again become the watchword. The Fifth Republic will be seen as no more effective than its many discarded predecessors. It is Mr Sarkozy’s agenda or, in effect, it is a Sixth Republic. The stakes are that high and, ultimately, that simple.

Napoleon Bonaparte, whom Mr Sarkozy cites as his hero (short men stick together), noted of his leadership that: “I am sometimes a fox and sometimes a lion. The whole secret of government is knowing when to be one or the other.” The new President will have to be as cunning. He needs to reconcile this fantastically creative but intensely stubborn nation with the realities of an international economy that does not allow for 35-hour weeks or one in four of the population claiming to be a farmer and looking for a subsidy. He will have to deal with opponents for whom the riot is a strategic weapon. He has to frame a foreign policy that is more sophisticated than the “Yanks, no thanks” message of the Chirac era. I do not know whether the French have an equivalent phrase to “last chance saloon” but right now, like it or not, they are drinking (decent plonk, doubtless) in it.

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