Fox News Channel host Bill O’Reilly and syndicated columnist and Fox News Contributor George Will engaged in a tense exchange over O’Reilly’s book “Killing Reagan” on Friday.

O’Reilly began by saying Will’s column accusing him of slandering Reagan was libel. O’Reilly then asked Will why he didn’t call him before running the column, as Michael Clemente told O’Reilly that Will told him. Will denied he ever made the promise, and said O’Reilly could have called him if he wanted to. Will added, “I’m saying either you’ve got it wrong, it would not be the first time you got something wrong, or it was a misunderstanding –.”

Although, after O’Reilly said he had the promise from Clemente in writing, Will stated there “was a misunderstanding.” O’Reilly argued that Will “had an obligation as a journalist” to call him first.

The discussion then turned to page 245 of the book, and it’s discussion of a March 2, 1987 meeting called by Reagan Chief of Staff Howard Baker, who O’Reilly said asked his assistant to investigate Reagan.

Will stated he wasn’t denying this was true, but accused O’Reilly having never seen the memo and never even asking to try to see until after the book was in print. Will didn’t deny the memo exists, but that Cannon repudiated and deny the memo that he says O’Reilly makes the centerpiece of the book.

O’Reilly maintained such a recanting was done “under heavy pressure.” Will laughed at O’Reilly for saying this, and maintained O’Reilly doesn’t know this.

After another exchange over the memo, O’Reilly said, “You are actively misleading the American people. You are lying.

Will shot back, “You’re something of an expert on actively misleading people.”

Will later asked why O’Reilly avoided asking certain people in the Reagan administration, which he said O’Reilly avoided doing “because they would have refuted the flimsy thesis you have.” O’Reilly maintained he doesn’t talk to people with “skin in the game.”

O’Reilly further maintained the book is “laudatory” towards Reagan, and accused Will of omitting that. Will countered, “It is not a laudatory book. It is doing the work of the left, which knows that in order to discredit conservatism, it must destroy Reagan’s reputation as a president and your book does the work of the American left, with its extreme recklessness.” Will also criticized O’Reilly for cancelling his interview with Ed Meese, which O’Reilly said happened Meese “wanted to come on with conditions.”

O’Reilly also said to Will, “You’re a hack. You are in with the cabal of the Reagan loyalists who don’t want the truth to be told.” Will asked, “Why do Reagan loyalists not want this laudatory book published?” O’Reilly shot back that the “Reagan loyalists” “wanted a deification.”

O’Reilly also accused these Reagan loyalists of trying to kill the book before its publication, which Will said was a lie. O’Reilly said he could prove it wasn’t and called Will a “hack.”

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