Even Hillary Clinton said it herself this weekend during a campaign rally in Dover, New Hampshire:

“If the most important thing to any of you is choosing someone who did not cast that vote or who has said his vote was a mistake, then there are others to choose from,” she said, a veiled reference to two of her rivals for the Democratic nomination — respectively, Senator Barack Obama of Illinois and former Senator John Edwards of North Carolina.

Bottom line: she will never apologize for her pro-war vote.  Progressives should stop thinking it will ever happen.  They should also stop expecting that as president, unlike George W. Bush, Clinton would have the humility to admit failure from time to time.