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Intended as an obvious "gotcha" question, Mr. Gibson asked her to describe the Bush doctrine. Only problem was - Gibson was wrong. The Bush doctrine had changed three times as the fluidity of the situation in the Middle East changed after 9/11.
The most recent National Security Strategy compiled by the National Security Council (Bush doctrine) can be found here.
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Mr. Gibson did not do his homework because he obviously thought the first National Security Strategy after 9/11 was 'cast in stone' and was never altered. He did not know it had been changed to match the ever-changing situation in the Middle East.
The Gibson interview probably wasn't the first time Sarah Palin had been talked down to by a condescending man trying to intimidate her while showing his superiority.
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As the interview progressed, Mr. Gibson looked more uneasy than Sarah Palin. One reason may have been his annoyance at the way Palin kept calling him Charlie - almost as if she were scolding a child for not cleaning his room.
Another reason for Gibson appearing ill as ease may have been the pressure on him by ABC to make Palin look like a naïve moose hunter and his inability to get the job done.
Anyway, Palin's intelligence and grace-under-fire during a "gotcha" interview won over many that were angered by her treatment.
More on how Charlie Gibson "got it wrong" is here in a report by Dr. Charles Krauthammer from the Washington Post.