That was his first mistake.  And Bill O’Reilly was about to make him pay for it with a dressing down rarely if ever seen between two conservative superstars on a major prime-time news show.

The clash began with George Will’s evisceration of O’Reilly’s new book, Killing Reagan.  O’Reilly documented how Reagan’s health was much worse than most knew.  So bad that staffers prepared a memo instructing Reagan’s chief of staff, Howard Baker, what to do if it was discovered the president was no longer able to carry out his duties.

Will did not like that on two counts.  One, it was untrue.  Two, it was unkind.  Will’s attack began with the Washington Post headline: “Bill O’Reilly Slanders Ronald Reagan.”

The rest of the review was reminiscent of Mary McCarthy quote of Lillian Hellman: “Every word she writes is a lie, including and and the.”

A few one-liners should capture Will’s unusually pugilistic approach:

Unsubstantiated assertions.

Fiction (refuted by minute-by-minute records in the Reagan Library.)

Pretense of scholarship.

This book is nonsensical history and execrable citizenship, and should come with a warning: “Caution -- you are about to enter a no-facts zone.”

Friday night, Will entered the No-Spin Zone to defend his take-down.  O’Reilly was ready.  Will, perhaps, was not.

O’Reilly launched one blistering attack after another.  But the real battle was over the centerpiece of O’Reilly’s book: what happened in a March 2, 1987 meeting in the White House, called by Howard Baker.

“Before the meeting took place, Howard Baker asked his assistant, James Cannon, to investigate Ronald Reagan,” O’Reilly said to Will. “Are you denying any of that is true?”

“Of course not,” Will said.  “You say that memo that he wrote is the centerpiece of a book.  It is a memo that you have never seen.  It’s a memo you never even asked to try to see from the Reagan library.”

If Will was expecting O’Reilly to wither, he got the opposite.  O’Reilly pressed on and said that lots of people had seen the mysterious memo.  Soon O’Reilly was quoting a Reagan confidant, the late Michael Deaver:

After a day and half of briefings, but without seeing the president, they delivered to Baker a stunning report: He would have to be prepared at any time to invoke the 25th Amendment, which would remove a president if he was unfit to serve. They had concluded the president was on the brink of being physically and mentally incapable of carrying out his responsibilities.

Will was not having any of it: The memo was less than it seems because after Baker glanced at it, he put it aside, and that “was the end of it,” Will said.

“That was not the end of it,” countered O’Reilly with a raised voice.  “You are misleading the American people.  You are lying.”

“You are something of an expert at actively misleading people,” countered Will.

“You are lying,” said O’Reilly, cutting off the dean of America’s conservative columnists.

By the time O’Reilly finished, the only thing Will could cling to was the idea that O’Reilly may have been unkind.  He may have done the work of the left wing in helping to discredit Reagan.  But untrue and undocumented?

That question was settled easily in O’Reilly’s favor.

After a bit more sparring, Will characterized O’Reilly’s research style as “extreme recklessness.”

O’Reilly counted by calling Will a liar and, with finality, “a hack.”

Then it was over.  And conservatives around America were trying to piece together what they had just seen.  Because no one could recall seeing anything quite like that before.