President Joe Biden threw one of GOP presidential nominee Donald Trump's favorite insults back at him during a speech at a union event in Pittsburgh on Saturday. Biden was discussing the importance of character at the event, hosted by the Laborers' International Union of North America, on Saturday night when he charged that the former president "doesn't give a damn about union workers " or any workers, for that matter." "He views unions as getting in the way of the accumulation of wealth for individuals," said Biden, who's called himself the "most pro-union president" in history. Folks, it's a laborer's interest to defeat Donald Trump more than any other race you've been in, as long as any one of you been alive," he added. Then he got a little more personal, as Trump often does. "Donald Trump is a loser," . "He's a loser as a candidate, and " more importantly, in my view, and I'm just going to say it, straight up: He's a loser as a man."