It's been called the "scream heard 'round the world." Now it's echoing in Pittsburgh. Howard Dean was the Democratic front-runner in the 2004 presidential campaign until he responded to losing the Iowa caucus with a frenzied speech and wild whoop. Instead of rallying his troops, Dean's rant on national TV became one of the most laughed-at moments in political history and took the steam out of the former Vermont governor's bid for the White House. Republicans plan to poke more fun at the episode when Dean, now chairman of the Democratic National Committee, appears today at a Democratic Party event...