There was much more that Howard Dean could have been nailed on more than the scream but that started a fad that gave them a "safe" way to tank him.
This let's people walk away from Election 2004 thinking he lost becuase of ONE lie. He was a traitor, possibly a war criminal, and IS a habitual liar. Some would rather let the skeletons of Vietnam remain buried.
Michael Dukakis never stood much of a chance but his failure is blamed on that stupid photo of him in a tank.
If Kerry's post service Vietnam past is not fully outed, he can still serve in the Senate. Heck, known traitors are probably okay there. Former KKK Kleegles are, just ask Robert Byrd.