The vice president donned a black-and-gold United Steelworkers union hat and told hundreds of union members that the gap between the wealthy and poor was hurting the nation.
"The tax code's not fair. It's simply not fair," Biden said in a city long associated with organized labor. "The wealthy aren't paying their fair share. There used to be one America."
Biden later marched throughout the city's downtown, hearing encouraging words along the parade route.