The French government of Dominique de Villepin has pinned its hopes of bringing back peace to the streets of Paris on a law dating from 1955.
The law was introduced to deal with trouble arising from the situation in Algeria by allowing local officials to introduce, among other things, curfews.
Given that many of the demonstrators who have thronged the streets of cities and towns across France in the past two weeks are the children and grandchildren of Algerian immigrants, there is a certain historical echo in that.
Most French people support the job the police are doing
But will the introduction of curfews work?
The experience of Raincy, a pleasant outer suburb of Paris, indicates that it just might. On Monday the mayor announced he was considering a curfew. Maybe people thought he meant it was already introduced.
By 2200, at all events, there was no sign of the gangs of young, restless people looking for targets for their anger who had roamed around on previous nights. A few cars drove up and down the main street. That was all.
No winding down
Other Paris suburbs where there has been violence recently were quiet too. Not completely - but then this is a country where even in normal times several dozen cars are set alight each week. The real violence happened elsewhere, and Paris breathed a sigh of relief.
The government did too. If the trouble has now started to burn itself out, then the government will certainly maintain that its firmness and its willingness to introduce strong measures like curfews have been responsible.
It is clear that the anger which has made these young, rootless, often uncontrollable kids into violent demonstrators is still there, as strong as ever
Yet when I went to the courthouse at Bobigny, not far from Raincy, I found a rather different picture.
The courts have been handing out tough sentences to convicted rioters - up to 10 months' jail for prisoners who are often just teenagers. Yet their friends were proud of what they had done, and strongly assured me that there was no question of winding down.
When I asked one 20-year-old, Khaled, what would happen if curfews were introduced, he laughed and said: "That's it - everyone will be out on the street with weapons."
No doubt that was just bravado. But it is clear that the anger which has made these young, rootless, often uncontrollable kids into violent demonstrators is still there, as strong as ever.
Stronger, perhaps. A woman of 24, heavily pregnant, came to the courtroom to find journalists who would be interested in watching a video she had made of the police coming to her flat to arrest her husband.
In fact he had been on night-shift, and not out in the streets at all - but the video showed how aggressive the police were, and there are dozens of accounts going the rounds of the police shouting at the demonstrators that they are "sales arabes", dirty Arabs.
Many of the rioters are proud of what they have done
The mother of one prisoner told me that the policeman who arrested her son had shouted that the boy ought to be sent home. "What home does he have but France?" she asked, tearfully.
Still, a large majority of French people support the police in the job they do, and the Interior Minister, Nicolas Sarkozy, has himself described the demonstrators as "rabble".
The crazy, uncontrollable violence of the past fortnight has persuaded a large number of people here that the only way to deal with rioters is to be tough with them. The introduction of selective curfews may work, but they won't do anything about the anger and the sense of alienation which have produced these ugly scenes.