In the space of five years, France has been shaken by three prolonged periods of street violence with radically different  causes and protagonists.

There were the provincial and outer suburban Gilets Jaunes riots of 2018-9, followed by the violent ultra-Left fringe of the anti- pension reform protests this year and in 2019.

The country is now into the fifth day of the most violent and widespread uprising in its multi-racial suburbs for 18 years. Of the three revolts, the present insurrection is perhaps the least surprising and the most worrying.

There are many fault-lines in French society but the deepest and most dangerous, the most misunderstood and potentially the most explosive is the invisible barrier which separates the mostly prosperous and white cities from their multi-racial inner suburbs or banlieues.

These suburbs are both better and worse than many who have never visited them imagine: an archipelago of poverty and creativity, energy and gang-warfare, hope and suffering. They contain millions of hard-working people without whom the prosperous cities could not survive. Every 10 to 20 years they explode like a not-quite-dormant volcano.

It is unclear whether this uprising will be more prolonged and more destructive than the three weeks of rioting which spread to almost every French city and medium-sized town in October and November 2005.

Those 2005 riots began slowly in the north Paris suburbs and spread gradually around the country, like a forest fire. The 2023 riots have exploded everywhere almost at once. They may, or may not, burn out more rapidly.

The advance of social media partly explains this difference. The video showing the inexplicable killing on Tuesday of 17-year-old Nahel by a traffic cop in the west Paris suburbs (six kilometres from the Arc de Triomphe) was seen within minutes on mobile phones in the cités (public housing estates) of Marseille, Toulouse, Bordeaux, Lille and Strasbourg.

Just as in 2005, the reaction has been largely one of mass self-harm – what the France football team (mostly born in suburban cités) called in an eloquent appeal for calm on Friday a “veritable process of auto-destruction.”

The rioters, many of them as young as 14, have attacked symbols of the state like police stations and town halls. But they have also burned their neighbours’ cars, vandalised the schools where they were educated and destroyed the trams and buses which their parents depend on to get to work.

This is not a monolithic nor an organised movement. It is an insurrection but not a revolution. It has no clear aims.

Many of the young people on the streets have been swept up into an orgy of violence they do not understand. Of the first dozen or so tried on Thursday in Nanterre, where the riots began, not one mentioned Nahel by name; none spoke of their fear or hatred of the police.

Some of the rioters are no doubt genuinely incensed by police violence and determined to avenge a “brother” they never met; others seem more interested in looting shopping centres.

There is some evidence of coordinated plans to attack town halls and police stations. There is also some evidence of the involvement of the mostly white, anarchist Black Bloc movement, which has been building support in the multi-racial suburbs in recent years.

But there is no single pattern or strategy. Many of the rioters belong to gangs which are in perennial, vicious warfare with gangs from neighbouring cites. They have joined forces temporarily as they did in 2005;  or more likely they are competing, housing estate by housing estate, town by town, to show which is the most angry and destructive.

Unlike in 2005, the rioting has crossed the invisible wall between banlieues and cities proper in the last two days. Cars have been torched and shops pillaged in central Paris, Lyon Strasbourg and Marseille. These incidents have been the work of relatively small bands (not all of them from the banlieues).

There are now appeals on social media for a mass attack on the Champs-Elysées on Saturday night. That may not materialise. Most of the young rioters prefer to remain on the territory they know. If the attack does happen, the insurrection will have mutated into a disturbing new phase.

But why such anger and violence?

It is wrong to say that nothing has changed in the banlieues since 2005. Billions of euros have been spent on improved housing and transport links (including the trams and buses burned by the rioters). More could certainly have been done. President Emmanuel Macron commissioned – and then rejected – plans for a more radical transformation of the poorest and most troubled suburban estates in 2018.  

What has not changed is the enmity (not too strong a word) between young people and the police. Not all the young people are angels; not all the police are racists. But a young person of North African or African origin is 20 times more likely to be stopped and questioned by police in France than a young white person.

The police face an impossible task in trying to contain the drugs-trading violence of suburban gangs – whose first victims are the majority of law-abiding residents of the banlieues. But those law-abiding citizens are often just as fearful of the police as they are of the gangs.

The flics are seen not as protectors, but a hostile, occupying force. Attempts to create a more local, neighbourhood system of policing were abandoned by Nicolas Sarkozy, as interior minister, two decades ago.

Racist, the French police? Not all of them. But the two biggest French police unions (which reject accusations of racism) exposed their own core attitudes in an extraordinary public statement on Friday. The statement spoke of the rioters as “vermin” (nuisibles) and “savage hordes” and warned that France was in the middle of a civil war.

There was no mention of the fact that an experienced and decorated police sergeant (brigadier) had initially lied in his official report on why he shot a 17-year-old Franco-Algerian boy in the chest after stopping him for multiple traffic offences on Tuesday morning.

The officer, in his second version of events which may well be true, says he meant to shoot Nahel in the leg but the car moved forward and jogged his arm. But why shoot him at all? It is an extraordinary fact that 17 people – mostly of African and North African origin – have been shot dead by police in France after refusing to stop their cars in the last 18 months.

There are several reasons to fear that the present riots could be more dangerous than those of 2005 – whether or not they burn out more rapidly.

The French political landscape is more fragmented than it was 18 years ago. Parts of the radical Left, starting with its leader Jean-Luc Mélenchon, have refused to appeal for “calm” and have all but approved the violence.

A more powerful, but divided, Far Right is trying to pour fuel on the flames by urging Macron and his government to crack down more violently on the rioters (as if the answer to an insurrection against police violence was more police violence).

Marine Le Pen, as part of her campaign to appear more respectable, has used relatively calm language. Not so her rival Eric Zemmour who talks of a revolt by “the foreign enclaves in our midst”.

Foreign? The teenagers on the streets are almost all French-born and belong to the second or third generation of migrant families.

Zemmour’s words, echoed in the readers’ comments in Le Figaro and elsewhere, are telling – and damning.

There are many causes of this revolt and there are  many faults on all sides. But core reason for the alienation of yet another generation of young people in the French banlieues is not simply police violence.

It is the knowledge that a large part of the rest of the population (not all) will never accept them as French.