When news of a terrorist beheading broke on June 26, the first reactions from residents of Saint Quentin Fallavier, a small town of 6,000 inhabitants, sounded terribly familiar: "We never thought this could happen here."
The same words were uttered by Parisians living in the quiet 11th arrondissement of the French capital where, on January 7, Islamist terrorists had first struck in a series of attacks which petrified the whole country. That day they killed 12 people -- cartoonists, journalists and two policemen at the offices of the French satirical weekly "Charlie Hebdo."
The Isere region, where today's attack occurred, is better known for its green scenery, mountainous landscape and canoeing than for the industrial factories such as Air Products, the industrial gas plant targeted by Yassin Sahli, the 35- year-old alleged author of the attack.
The suspected terrorist had been the object of surveillance from France's anti-terrorism special unit between 2006 and 2008, but had no criminal record.
Such details highlight the extraordinary difficulty in which French police, and European anti-terrorism forces in general, find themselves. Social networks have been quick to question why authorities failed to foil yet another attack in time.
However, such acts are being prevented every month without the wider public being informed until the threat has been neutralized.
A majority of French people feel both powerless and frustrated in front of a menace whose nature is by definition to be unpredictable and to strike at the heart of society.
The grim discovery of a severed head put up on the railings of the factory with Arabic inscriptions on it has sent shockwaves through France.
President Hollande, who had to leave the EU Summit in Brussels, to attend an emergency meeting at the Elysees Palace in Paris, also recalled his prime minister who was about to embark on a four day official visit to Colombia and Ecuador. Since the January attacks, France has been on the highest level of its anti-terrorist system "Vigipirate." The army has been patrolling the streets of Paris, while armed soldiers guard landmark buildings as well as Jewish cultural centers and schools throughout France.
There will be concerns among the Muslim population in France that the latest terrorist attack may whip up anti-Muslim feeling in the country.
However it comes a week after France's Interior Minister, Bernard Cazeneuve, revealed new measures to counteract Islamophobia: the systematic listing of all Islamophobic acts, and a campaign of information to encourage victims of such acts to come forward and file a complaint with the police.
At Easter, the French were reminded of the importance of remaining in a state of "enhanced vigilance" as Manuel Valls put it, after they learned that an attack on two Catholic churches in Villejuif just outside of Paris had been thwarted completely by chance (the perpetrator having shot himself in the leg on his way to Villejuif and having had to call an ambulance which in turn called the police).
After today's attack, the French Parliament will have no qualms in passing the surveillance laws that "The New York Times" recently highly criticized: "French Parliament is overwhelmingly approving a bill that could give the authorities their most intrusive domestic spying abilities ever, with almost no judicial oversight."
But in the current context, few French people are likely to raise an eyebrow at the new measures. The French have traditionally been more trusting of the State than, for instance, their British or American counterparts.
As a nation, they will consider it a necessity to have full power to spy on an enemy defined by its violence and non-traceability.
Agnes Poirier is a French journalist and political analyst who contributes regularly to newspapers, magazines and TV in the UK, U.S., France, Italy. The opinions expressed in this commentary are solely those of the author.