Donald Trump has shocked France. The American president laments the disappearance of an eternal Paris, while U.S. immigration officers detain French researchers at the border.

It all started when Donald Trump declared that Americans should not visit France. The Potus said his (probably non-existent) friend, “Jim,” had told him he would no longer be visiting the French capital because “Paris wasn’t Paris anymore.” The message is little more than common prejudice. The perfect Paris dreamed up by Jim (A.K.A. Donald) is supposedly filled with “born-and-bred” French people — a favorite term used by the Front National to avoid saying “white” — all sporting berets, moustaches and baguettes. This timeless Paris is a well-rooted ideal held by Americans who know little or nothing about France. Woody Allen represents this Paris in his films, but freely admits he never strays out of the 8th and 16th arrondissements. This fantasy city is also the subject of works by “writers” such as Pamela Druckerman (Bringing up Bébé) and Mireille Guiliano (French Women Don’t Get Fat). Apparently, these authors have never set foot in the north or the east of the capital, whose neighborhoods are now as cosmopolitan as New York.

I remember watching Laurent Cantet’s film The Class in Manhattan. The movie tells the true story of a philosophy teacher in a Parisian high school in the 20th arrondissement. A large number of his students come from Africa, and have difficulty speaking French and mastering the vocabulary of Descartes. Americans in the audience asked me if the film was really set in Paris. Upon hearing that it indeed was, they exclaimed: “So Paris is just like the Bronx!” Perhaps Jim was in the theater that evening. Paris has become a globalized, cosmopolitan city, which makes it even livelier and less traditional. It’s safe to say that Jim — just like Donald and certain French people — don’t like immigrants of color ruining their little fantasy.

These anecdotes take a more serious turn with the misfortune of Henry Rousso. The French historian and Holocaust expert is renowned in our two countries, and was invited to a conference at Texas A&M University. But on his way to the event, he was detained at Houston airport on February 22. Immigration officers revented him from entering the country for ten hours, on the pretext that Henry only had a tourist visa, despite coming to talk at a conference. In this case, they claimed, he should have had a work visa. This argument has no legal grounding, and if it were true it would prevent any academic dialogue and university conferences between France and America. The president of the university and a team of lawyers had to intervene to obtain Henry’s freedom. The immigration department put the mistake down to the “inexperience” of one of their officers.

It was Henry’s birthplace, in Cairo, which set off his interrogation. “How could he be both French and born in Cairo?” And this is not an isolated case. The vice-president of the pharmaceutical laboratory Novartis was recently detained at Kennedy Airport, where he had to explain why he was French but born in Algeria. Donald and Jim should understand that you can be French and born elsewhere. You can even be black or Arabic. But perhaps Donald and Jim prefer “alternative facts” to the truth.