The angle I find particularly fascinating is the one illuminated by Gore's treatment of Joe Lieberman, also a Democratic candidate. Never mind the spectacular ungraciousness of Gore not giving his 2000 runningmate the courtesy of a phone call - Lieberman learned of Gore's endorsement from the press.
Instead, think about what this says about a man who spent almost his entire life running for president as a moderate, reasonable centrist in the "New Democrat" mold.
In 2000 Al Gore insisted that Joe Lieberman was the most qualified man to fill his shoes should a President Gore be unable to complete his term. Obviously, politics were a consideration, but Gore nonetheless made the plausible and necessary case that Lieberman was the best man to take his place.
Since then we've been brutally attacked on our own soil, we've fought two conventional wars and we are continuing to fight a third on global terrorism. In the time since then, Joe Lieberman has been at the forefront of the war on terrorism in the Senate. He was pretty much the original drafter of the Department of Homeland Security, and in 2001 and 2002 he was the chairman of the Senate Governmental Affairs committee. In short, not only is Lieberman more qualified than he was in 2000, but the things that made him qualified to be Al Gore's stand-in back then are all the more important after 9/11.
Meanwhile, Howard Dean was still an ex-governor of the second smallest state in 2000 and nothing he's done since then has made him any more qualified to be president. Like many of his fellow contenders, he sees the war on terrorism as a law enforcement issue. He sees nation-building (once an important issue for Gore) in Iraq to be so much imperial folly. Dean ridicules pretty much all of the centrist positions on defense and domestic policy that both Gore and Lieberman used to be synonymous with.
I understand Gore sees in Dean one qualification Lieberman doesn't have: the potential to win. But when you think about all that has happened since 9/11, for Gore to say that the post-9/11 world makes Howard Dean more, not less, qualified to be president than Joe Lieberman really shows how unserious Al Gore and his party have become.