The first time the GOP nominated Bush 41 there were many early suggestions he was weak (IMHO, the flip side of Dole being characterized as vicious during the primary.) He evidently decided to dispel those rumors by lashing out at Dan Rather during an interview, and it seemed to work. I don't think Rather forgot it though, and it may have made him a bit overeager to accept the memos received in 2004 purporting to show Bush 43s National Guard commander had never seen him. In defense of Rather on that occasion, CBS vetted those memos with the White House itself beforehand, and it said they didn't look fake (personally I think they set him up, but who knows?) Dan Rather is surely as familiar with the Bush family as all our fellow Texans are, and his impression of them is clearly unfavorable.