New York Magazine's Gabriel Sherman highlighted the ongoing “civil war” between Fox News host Bill O'Reilly and contributor George Will over O'Reilly's newest book, Killing Reagan, in a new report. Sherman interviewed executives at the network who call O'Reilly's books “a joke” and offered insight on a feud between Fox executives Bill Shine and Mike Clemente.

The recent feud began after Will published a November 5 Washington Post column titled, “Bill O'Reilly slanders Ronald Reagan.” In the column, Will called the book “nonsensical history and execrable citizenship,” with a “preposterous premise” that “should come with a warning: 'Caution -- you are about to enter a no-facts zone.'”

O'Reilly responded to Will's column later that night, calling it “libel,” and challenged Will to come onto his show and attack him in person - a challenge Will accepted.

Sherman's November 9 exclusive highlighted the “civil war” currently raging at Fox, noting the distain for O'Reilly and his Killing books and how the rift has strengthened the rivalry between Mike Clemente, who oversees the news division, and Bill Shine, who oversees the prime-time shows. Both are high level executives hoping to replace Fox News Chairman and CEO Roger Ailes. According to Sherman, a Fox executive also commented O'Reilly's Killing series of books are considered “something of a joke inside the network,” with the executive saying, "[O'Reilly] certainly doesn't research his books":

Inside Fox, the O'Reilly-Will feud is being closely studied by executives because it is part of a larger power struggle that's taking place at the highest reaches of the organization. On opposing sides of the fault line are Clemente, who oversees news (where Will works), and executive vice-president Bill Shine, who oversees prime-time shows (where O'Reilly works). Clemente and Shine are vying to replace Ailes and are such bitter rivals that they barely speak, numerous Fox employees say. In August 2014, the rivalry intensified when Ailes put Shine in charge of the Fox Business Network. “This is some Game of Thrones shit,” one insider told me. The relationship is so bad that Clemente is not involved at all in preparing for the upcoming GOP debate on Fox Business.

Shine's loyalists tell me that Clemente did not confer with Shine about Will's anti-O'Reilly column before it was published. Furthermore, they're furious at Clemente for not stopping Will from embarrassing Fox's highest-rated host in the pages of the Post. They reminded me that it was Clemente who recruited Will to Fox from ABC in 2013. One source also explained that Will received a special contributor contract with Fox that grants him editorial independence for his column (other contributors are barred from writing about Fox without permission). “He doesn't have to check with Fox,” the source said.

Clemente did not comment, but his camp is firing back off the record. “Almost everyone is on team George,” one said. “Everyone is snickering and thinks it's a riot.” Another told me that O'Reilly's Killing series is considered something of a joke inside the network. “He certainly doesn't research his books,” one executive said.

Where Ailes stands remains unclear. In the past he's been critical of O'Reilly's book-writing ventures. In my biography of Ailes, I reported Ailes told colleagues that O'Reilly is “a book salesman with a TV show.” Fox News has not commented on the mess. “Roger is probably in the men's room hoping this whole thing blows over,” one insider told me today. That might be wishful thinking. The rumor at Fox is that Will is preparing to write another O'Reilly column. Will did not respond to requests for comment.