Just after 10am on Wednesday, when Laurence Turbec opened the service door of a McDonald's restaurant near Dinan, Breton terrorism came of age.
Several sticks of dynamite exploded at her feet, cutting her in two, and hurling her shattered remains into the bushes beside the drive-through lane.
All the indications are that this was a clumsy mistake. Breton terrorists had never previously killed anyone but themselves.
Police believe the dynamite was supposed to have been triggered, innocuously, in the early hours by a home-made device, based on an ordinary kitchen timer. The timer failed to detonate, as did a similar device left outside the post office in Rennes, 30 miles to the south, the same night. The Rennes bomb was found and defused; the McDonald's bomb exploded accidentally when Ms Turbec, 28, opened the door to put out the dustbins.
The shedding of innocent blood is, nonetheless, a rubicon in French-Breton politics. It is a perverse, inescapable fact that the murder of Ms Turbec produced a greater torrent of words about Breton independence in French and foreign newspapers than has ever appeared at one time before.
French anti-terrorist experts fear that, having killed once, the extremists may be tempted to pursue the logic of this blunderingly effective exercise in self-advertisement. On the other hand, Ms Turbec's death seems to have genuinely outraged many fellow travellers on the more doubtful fringes of Breton activism.
The occasional plasticage (bombing) of a government building in the dead of night has long been acceptable to the tiny number of Bretons who support outright separatist causes. Ms Turbec's death was not. The several extremist political movements admit that, since Wednesday, they have been called by many of their supporters threatening to cut off all contacts.
All "mainstream" democratic Breton nationalist organisations - from the moderate, socialist Union DÃ©mocratique Bretonne to the pro-outright-independence Parti pour l'Organisation d'une Bretagne Libre - condemned the bombing as an outrage and betrayal.
To put the Breton movement in perspective, these "mainstream" parties command no more than 3 to 4 per cent of the Breton vote. Breton nationalism suffered a devastating blow when its leaders threw in their lot with Nazism during the German occupation of France.
A majority of the 2,800,000 Bretons now identify with "cultural" causes such as support for the Breton language, greater regional autonomy and the return of the "lost" area of Loire-Atlantique around Nantes, excluded from Brittany by Parisian planners. Very few Bretons support any serious degree of separation from France.
The Bretonnist movement is itself divided into five or six often mutually hating fragments. French authorities believe that the Dinan bombing was the work of the ArmÃ©e RÃ©volutionnaire Bretonne, which probably has no more than a dozen active members, separated into two cells.
Security officials admit that they have regarded the ARB as a joke, because of its amateurism and self-imposed efforts not to kill anyone. On one occasion, supporters were arrested after paying for a 27 franc (£2.50) detonating device with a personal cheque.
Surveillance was slacker than it should have been, despite indications that a new, more militant generation has taken over the ARB. There have been signs of a revival of old links with Eta, the Basque terrorist movement, which is both professional and unscrupulous about loss of life. The dynamite from the Dinan and Rennes bombs came from a consignment of eight tons of explosives, stolen in what was probably a joint ETA-ARB operation last September.
At the same time, the ARB has been drifting away from the traditional Bretonnist grievances - language, culture, Parisian arrogance - towards a trendier mix of anti-capitalist, anti-globalist, and environmental causes. Hence the tortured logic which makes Ronald McDonald an enemy of Breton autonomy.
Jean GuÃ©guÃ©niat, a moderate Breton nationalist town councillor in Brest, blames the emergence of a new "irresponsible" and younger strain of Breton nationalism, "influenced by a pseudo-Irish romanticism" and determined to distance itself from the far-right connections of the past. "Let's hope they've learned a lesson," he said.
If not, he pointed out, with four tons of the stolen dynamite still unrecovered, the ARB has enough firepower for 100 further bombings.Reuse content