Because the anti-war left is trying to use the "no link between terrorists adn Saddam" as proof that we should never have gone into Iraq, that Bush wanted to go into Iraq, "for oil" and that people should vote for the Dems this fall.
The Democrats' opinions are frequently deliberate lies designed to hide the truth. The Soviet Union used the same approach in its attempt to undermine free countries. It's been plain that Democrats are socialists; now they are Stalinists too.