In 2000, Al Gore was just being a smug jerk trying to rattle George W. Bush. Gore also probably thought he was off-camera. Biden was obviously trying to rattle Ryan, but he also knew the camera would be on him, so other than hoping to distract the audience so they wouldn't hear Ryan's superior arguments, I have no idea what this debate game-plan was intended to accomplish.
My guess is that Team Obama simply didn't expect moderator Martha Raddatz (who might be the worst debate moderator in history) to open things with a serious topic like foreign policy -- and this is where Biden got in trouble, even with left-wingers like Tom Brokaw:
It's actually unfortunate for Team Obama that The Worst Debate Moderator In History didn't, you know, moderate. Had she actually done her job and stopped Biden from interrupting Ryan some 82 times, Biden would've come off better.
Of course, no moderator could've stopped Biden from making his bigest mistake -- continuing the serial lies coming out of the White House about Libya.
Essentially what you had here was a fool acting the fool to distract away from the fact that (other than a trillion dollar tax increase) Obama has absolutely no second-term agenda and no credible way to defend the last four years.
When you got nothing, you act the clown.
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