Why France? Why has the home of the Enlightenment, of liberty, equality and fraternity become the prime western target for terrorists acting in the name of Isis?
The more determined President François Hollande sounds in declaring "war" on terrorism — as he did again after the murder on Tuesday of Jacques Hamel, an 85-year-old Catholic priest, made to kneel in his church before having his throat cut — the worse the threat appears to become. The state of emergency declared after the slaughter in Paris last November has not prevented further atrocities, including the deaths of 84 people in the Bastille Day attack in Nice or the stabbing of two police officers in front of their three-year-old son.
The medicine applied by the government since the attacks on the Charlie Hebdo magazine and a Jewish supermarket in Paris in January 2015 has clearly not been effective — although Manuel Valls, the prime minister, says that 15 attempted attacks have been thwarted since 2013. The opposition has suggested some radical measures but the basic question as to why these attacks keep happening has yet to receive a plausible answer.
Mr Hollande maintains that Isis targets France because it wants to destroy the values of civilisation the country embodies. That is no doubt true, though other western nations exhibit the same way of life denounced by the extremists.
Rather, a concatenation of several factors helps to explain why France remains the jihadis’ favourite target. To start with, the bombing of Isis bases inevitably attracts a response. This is the price of the firm action that Mr Hollande has espoused but which has not slowed down the pace of terrorist attacks on French soil.
Then there are the radicals of north African descent who have left France for Syria and Iraq, and are reliably reported to hold important positions in the Isis command structure. They are said to have maintained links with the "soldiers" who went to the Middle East and then returned to France to perpetrate the attacks in Paris last year.
Isis planners also appear to see an opportunity to drive a wedge between those in France, like Mr Hollande, who reject the most hardline security policies in the name of republican values, and those who call for Israeli-style measures. The potential for fostering political, ideological and indeed ethno-religious conflict ahead of next year’s presidential election is considerable.
Mr Valls said that the aim of those who murdered Father Hamel on Tuesday was to provoke a “religious war” in France. If there are economists in the Isis high command, they may also be counting on the attack to hit France’s status as the world’s leading tourist destination. Air France, reporting a 5 per cent revenue drop this week, pointed to “special concern” about the country among travellers.
There is also a more longstanding reason why such factors have come into play so powerfully in France. Twenty years ago, I spent time on some of the suburban housing estates that encircle Paris. The alienation — captured in Mathieu Kassovitz’s seminal 1995 film, La Haine — of the young people who lived on these estates, many of them immigrants or the children of immigrants, was striking even then. It has only intensified since as high levels of unemployment and crime have dogged the banlieues.
Successive governments have failed to get to grips with the grievances of the children of the north Africans who came to France in more prosperous times. Neglect has been the order of the day. When, around the turn of the century, I raised the problem with ministers, they waved it away. “Those young men have only to become good Frenchmen,” one official remarked.
As a result, the gap between the France that holds itself up as a shining light for the rest of the world and the reality of life on the estates has deepened. The result is a rejection of the republic by young people who feel it is at best irrelevant to them, and at worst actively hostile. This, in turn, creates a climate in which a man like Mohamed Lahouaiej Bouhlel, the Nice killer, finds a home for his turbulent instincts in Isis propaganda.
After the Charlie Hebdo attack, Mr Valls spoke of “territorial, social and ethnic apartheid” in France and “unbearable discrimination”. Now he and Mr Hollande strike a more martial tone. But the drumbeats emanating from the Elysée obscure the fundamental reason France is now in the grip of this reign of terror: the state demands allegiance to its lay republican principles, including the ban on Islamic veils in public places; but a minority of the population rejects that demand, sometimes violently. The tragedy is that, while the problem can be identified, the solution grows ever more elusive.
The writer is author of ‘The History of Modern France’, newly published in paperback updated to cover the terrorist attacks of this summer