French President Emmanuel Macron with President Trump in Paris on July 14. (Christophe Archambault/AFP/Getty Images)

BERLIN — European commentary on President Trump is rarely flattering, but the cascading revelations alleged in Michael Wolff’s tell-all book “Fire and Fury,” drew an especially fierce response from a horrified continent this week.
“Is Trump still sane?” asked the Friday lead headline on the site of Germany’s most respected conservative paper, Frankfurter Allgemeine Zeitung. The piece was published under the topic “mental health.”
Meanwhile, British readers woke up to the Times of London's main front page headline that also wondered about the president’s stability: “Trump’s mental health questioned by top aide.”
“Donald Trump’s right-hand man openly questioned his fitness to serve and predicted that he would resign to avoid being removed by his own cabinet, according to a book that the US president tried to block yesterday,” wrote the Rupert Murdoch-controlled Times of London.
For its part, France’s paper of record, Le Monde, just described the book as “haunting.”
Trump has never been too popular in Western Europe, with approval ratings in many countries hovering in the single or lower double digits. But even though disagreement with Trump has almost become the norm here, some of Friday’s public responses to Wolff’s book still appeared unprecedented.
The Times of London and the Frankfurter Allgemeine Zeitung are some of Europe’s most renowned news outlets, and both pride themselves with having especially influential readers in business and government in their respective countries  where conservative parties are in power. More so than in the United States, European papers frequently mix traditional reporting and editorials on front pages — often helping to sway public opinion, and by extension governmental strategy, as well.
Trump on Wolff's reporting: 'It’s in his imagination'
A degree of skepticism over the mental health fears prominently featured in Europe on Friday is certainly warranted, especially given that my colleagues have pointed out several possible flaws in Wolff's book and previous accusations against the author over alleged inaccuracies in his reporting. Trump himself has pushed back hard against the book, describing it as “full of lies, misrepresentations and sources that don’t exist.” His legal team has also threatened libel charges against Wolff, his publisher and Trump's former chief strategist, Stephen K. Bannon, whose no-holds-barred remarks are prominently featured in the book.
On Saturday morning, Trump took to Twitter to respond to questions raised over his mental health, and boasted about being "like, really smart" and a "very stable genius."