If you want a reminder of how fractious life can feel in modern-day Europe, then take a look at the furious row in France over the writings of Kamel Daoud.
Kamel Daoud is the Algerian novelist who came within an ace of winning France's top book award - the Goncourt - last year for his Camus-inspired The Meursault Investigation.
He is also an independent-minded newspaper journalist, who has won as many enemies as friends over the years for his critical articles about the state of his country.
But Kamel Daoud has now announced to the world that he is giving up his newspaper work, and will focus on fiction.
Why? Because of the frenzied reaction to a piece he wrote in Le Monde concerning New Year's Eve in Cologne.
The article in question - entitled "Cologne - City of Illusions" - was a two-pronged attack on the cliches triggered by the mass molestations of women.
On the one hand Daoud deplored the far-right "illusion" which treats all immigrants as potential rapists.
But by far the greater part of his anger was directed at the "naive" political left, who in his view deliberately ignore the cultural gulf separating the Arab-Muslim world from Europe.
Thus, according to Daoud, Europe welcomes immigrants with visas and material sustenance - but without addressing what really counts, which is the world of values.
What Cologne showed, says Daoud, is how sex is "the greatest misery in the world of Allah".
"So is the refugee 'savage'? No. But he is different. And giving him papers and a place in a hostel is not enough. It is not just the physical body that needs asylum. It is also the soul that needs to be persuaded to change.
"This Other (the immigrant) comes from a vast, appalling, painful universe - an Arab-Muslim world full of sexual misery, with its sick relationship towards woman, the human body, desire. Merely taking him in is not a cure."
These were strong words, and the reaction came fast.
In an opinion piece also in Le Monde, a collective of intellectuals and academics delivered an excoriating attack on Daoud, whom they accused of "feeding the Islamophobic fantasies of a growing part of the European population."
Daoud, the authors said, had based his argument on a discredited "culturist" analysis. In other words, he made Arab-Muslim culture the determining agent in the behaviour of individuals - turning them into little more than "zombies".
Worse, his call for immigrants to be taught western values was a form of "re-education".
"The whole project is scandalous, and not only because of the same old claptrap about the West's mission to civilise and its superior values.
"More than just the usual colonial paternalism… (Daoud) is effectively saying that the deviant culture of this mass of Muslims is a danger for Europe."
But worse was to come for Daoud: the row then spread to the US.
Last year Adam Shatz, a leading liberal journalist and editor, wrote a long and favourable profile of Daoud for the New York Times.
But now - regretfully but firmly - he turned against him.
"It is very hard for me to imagine that you truly believe what you have written. This is not the Kamel Daoud that I know," Shatz wrote in an open letter.
What worried Shatz - like the intellectuals (though he hated their "Soviet"-style public denunciation) - was the link Daoud drew between the events in Cologne and Islam.
"A few years ago we saw similar events at the Puerto Rico Day parade in New York. There too women were molested. But the molesters were not under the influence of Islam, but of alcohol," he wrote.
Shatz disputed the idea that sexuality in the Arab-Muslim world is universally a "misery".
And he was appalled by the implication that immigrant attitudes to sex and women were a "sickness" to be "cured". The same language, he said, was once applied to Jews.
Born in Algeria on 17 June 1970.
Edits the French-language daily Le quotidien d'Oran, for which he writes a column, "Raina Raikoum" (My Opinion, Your Opinion).
His debut novel, The Meursault Investigation won the Prix Goncourt du Premier Roman (Goncourt Prize for a first novel).
It is a retelling of Albert Camus's 1942 classic, The Stranger, from the perspective of the brother of the Arab killed by Meursault, Camus's antihero.
Across social media, the arguments have been raging.
For some, Daoud is a hero for speaking unpleasant truths about the culture of North Africa and the Middle East - doubly a hero for saying it not from exile but from his home in Oran.
But for his enemies, Daoud is a self-hating Arab who prefers French culture to Algerian, and whose attacks on religion are part-motivated by his own erstwhile flirtation with Islamism. (In the 1980s he was a young militant.)
Worse, they say his arguments play into the hands of the anti-immigrants in Europe who can now use them to nurse their own "illusions".
Daoud says he has had enough.
In an open letter to Shatz (a friend whose criticisms he respects), he denounces the academics and intellectuals who earlier denounced him.
"They do not live in my flesh or in my land, and I find it illegitimate - not to say scandalous - that certain people accuse me of Islamophobia from the safety and comfort of their western cafes."
And that is his last word.