Leading article: A new challenge, but also an opportunity

For the second time this winter, France seems to be experiencing a fast rewind of its recent past. First it was the transport strikes paralysing Paris. Now it is rioting by the young population of the capital's benighted banlieues. Both present a warning to President Sarkozy – and an opportunity.

The strikes are now petering out, underlining the stark differences between now and 1995, when the recently elected Jacques Chirac first challenged the vested interests of public service workers. With his solid electoral mandate, his personal determination and his semblance of tactical detachment, M. Sarkozy has compelled the once-powerful trade unions to recognise a new balance of forces.

The question now is not whether the unions will accept curbs on their members' privileges, but what the precise terms will be. Away in China when the protests began to wane, the returning M. Sarkozy must be careful not to gloat, especially as one of the more menacing ghosts of his time as interior minister in the Chirac government – banlieues violence – has returned to haunt him. The deaths of two teenagers, killed when a speeding police car hit the mini-motorbike they were riding, has so far sparked three nights of rioting in the suburban estates to the north-east of Paris. The incident happened not far from Clichy-sous-Bois, where the riots of two years ago began. The police, seen as hostile and racially prejudiced by many of the second- and third-generation North Africans who populate the estates, are once again the target.

There is little love lost between these "children of the banlieues" and M. Sarkozy. At the presidential election, they rallied in droves to the Socialist candidate, Segolene Royal, largely to express their fury with M. Sarkozy, who had referred to them during the 2005 riots with a French slang word widely translated as "scum". M. Sarkozy's background as a successful son of aristocratic immigrants did nothing to endear him to them either.

Yet this recurrence of violence gives the French President a chance to show, first, that he has learnt from his dismissive heavy-handedness of two years ago and, second, that he intends to live up to the socially inclusive ideals he espoused during his campaign. Above all, he has to demonstrate that the much-vaunted diversity of his Cabinet is not just for show.

Promisingly, one of the complaints voiced most often in relation to the latest violence concerns not the overbearing presence of police, but the lawlessness fostered by their absence. People living in these estates feel abandoned. M. Sarkozy must apply the same tactical skill and determination to bringing the banlieues into the French mainstream as he did to curbing the transport unions' outdated privileges.