In short, the New Atheists have won applause from the wrong side: the anti-Muslim, crusading Right. Christopher Hitchens, an endlessly entertaining writer who could give it to Saddam Hussein as good as anyone, was every right-winger’s favorite radical. Sam Harris started finding agreement with the likes of Douglas Murray and Ayaan Hirsi Ali. Rich Lowry’s defense of Harris from Ben Affleck appeared in the New York Post. Bill Maher now delights the Right as much as he infuriates it. And the Left, smelling traitors in its midst, simply cannot tolerate this sort of transgression.

But more attention is needed to the specific nature of the Left’s double standard when it comes to Islam. Why must ardent secularists from the Islamic world like Ayaan Hirsi Ali — the type of people the Left looks to for inspiration in the history of Western secularism — be deemed bigots, while Sharia-supporting conspiracy theorists like Linda Sarsour are cherished? Why has criticizing Islam caused the New Atheists to cross a red line in the progressive imagination?

These positions make no sense if one thinks of the Left as seriously secular, convinced of the need to end the reign of superstition. But American liberals profess neither the passionate skepticism of David Hume nor the honest, urgent atheism of Nietzsche. They prefer to embrace a shallow, culture-war atheism instead.