It could happen only in France and it is, in many ways, to the great credit of France that it should be so. It may be, however, that the greatest short-term beneficiary will be - perversely - Jean Marie Le Pen's Front National.
The French intelligentsia - unflatteringly labelled in Britain the chattering classes - have mobilised in the last week on a scale, and with an intensity of purpose, not seen in years.
An avalanche of petitions, signed by thousands of people, has engulfed the French government. Most of the signatories belong vaguely to the centre- left, but by no means all. Many are previously politically inactive. All declare a willingness to go to jail rather than obey a proposed new law against illegal immigration (no such penalty is actually envisaged, but no matter).
The signatories range from the internationally celebrated - such as Catherine Deneuve, Isabelle Huppert, Jeanne Moreau, Bertrand Tavernier - to the proudly obscure. One petition is entitled "121 people with names difficult to pronounce". Another is called the "appeal of the unknowns of Sauveterre- de-Rouergue".
Although their notional target is the clumsy new immigration law, due to be finalised next week, their fundamental objective is clear: to make a ringing declaration against the ultra-right, xenophobic Front National, following its electoral triumph in Vitrolles, near Marseilles, earlier this month.
The theatre director, Ariane Mnouchkine, said: "We are witnessing something very beautiful. A moral revolt against a France afflicted by the gangrene of the extreme-right."
The centre-right government of the Prime Minister, Alain Juppe, has responded in the way it generally responds to determined protest. It has given ground and hopes the problem will go away. It has agreed to scrap the most contentious clause in the new bill: a requirement that French citizens housing certain categories of foreigners should inform the authorities when the visitors move on. (This, it was claimed, would turn France into a nation of racist police spies).
The government concession has been contemptuously rejected as insufficient. The petitions - 45 major ones in Paris to date and scores more from the provinces - are still piling up: from statisticians, archaeologists, graphic designers, photographers, cinema owners... A large demonstration of people in expensive coats is planned in Paris tomorrow.
The French intelligentsia, depressed by the betrayals and failures of Mitterrandism, had fallen into a kind of apolitical trance in recent years. They have abruptly awoken, spoiling for a fight. The result in Vitrolles shocked them; the immigration law gave them a ready-made cause (no matter that it amounted to a tighter rewording of a law introduced by the Socialists 15 years ago).
President Jacques Chirac, a wily reader of the national political mood, is said to be deeply concerned about the consequences for his own ramshackle centre-right coalition in next year's parliamentary elections. The Socialist Party leader, Lionel Jospin, ignored the protests at first, but is now huffing and puffing to catch up with his own potential troops.
It all began on Wednesday of last week when 59 movie directors published the first petition, rapidly followed by writers, lawyers and journalists. The movement burst into flames on Sunday with the presentation of a petition from 402 actors.
The leaders of the revolt are mostly young and up-and-coming and not linked to any specific party or ideology. Deeply French, they are also citizens of a cultural and commercial world sans frontieres: precisely the world that fills the potential FN voters, and many other French people, with dread.
By seizing on the immigration bill as their cause, they are vulnerable to the standard accusation of the Front National: that the intellectual elite is more concerned about foreigners than the French. The immigration bill, though badly drafted and much amended, is not the Draconian instrument the petitioners complain of.
Out in the suburbs beyond the peripherique motorway, illegal immigration is a genuine problem, for French citizens and legitimate immigrants alike. Nothing in the protesters' rhetoric recognises such a legitimate anxiety.
In the tactical short term, Jean-Marie Le Pen has every reason to smile - the petitions have placed immigration at the centre of the political debate. They have also severely restricted the room for anti-Front manoeuvres of Messrs Chirac and Juppe.
But in the longer run, the protest is a healthy reminder of the attachment to humanist values in France. Vitrolles was a warning of the FN's strength. The speed with which the petition brush fire moved from the arts, through the professions, and into the provinces, is a reminder of its ultimate weakness.