To some, the bigoted nature of Charlie Hebdo’s cartoons is clear. “It’s a racist publication,” Ms. Prose, a former president of PEN, told The Nation last week. “Let’s not beat about the bush.”

The writer Luc Sante, who also signed the letter of protest, said that while the work of Georges Wolinski, one of the cartoonists killed in the attack, “was humane and large-spirited,” some of Charlie Hedbo’s contributors trafficked in “sophomoric troll humor.”

“The fact alone that black and Arab people are offended by the way they were depicted — leaving religion to the side — should have made PEN think before celebrating Charlie Hebdo,” Mr. Sante said in an email.

Defenders of the award counter that such arguments overlook the full scope and context of Charlie Hebdo’s cartoons. They point to websites like Understanding Charlie Hebdo Cartoons, which offers detailed analysis of some of the magazine’s ruder images, or to a study published in Le Monde in February stating that, contrary to the notion that the publication focused obsessively on Islam, fewer than 2 percent of the magazine’s covers between 2005 and 2015 primarily mocked Islam.

Adam Gopnik, a writer for The New Yorker (and a gala table host) who wrote an essay in defense of the award, said in an interview that the critics had elided the crucial distinction between blasphemy, which attacks a belief system, and racism, which attacks people.

“In France, it’s well understood that Charlie Hebdo was and is aggressively blasphemous and anti-religious,” he said. But “if you make a minimal effort to understand Charlie Hebdo in its proper context, you cannot conclude they are racist in any meaning of the term.”

The conversation about Charlie Hebdo in France has indeed been different from those in the United States. There, the magazine is widely seen as a leftist, anti-establishment irritant and champion of the underdog, carrying on a long French tradition of scabrous satire. The former President Nicolas Sarkozy was a particularly despised target, and the magazine has been unsparing in its evisceration of the right-wing, anti-immigrant National Front.