Labor: Union bosses have contended for some time that a secret ballot isn't needed to unionize a workplace. All that's needed, they said, was employees' signatures on cards. But Chattanooga proved them wrong. For months the United Auto Workers have said a majority of workers at the Volkswagen plant in Tennessee had signed cards expressing their interest in unionizing. Why bother with a secret ballot when the workers had already spoken through the "card check" approval process? Before a much-anticipated and widely followed union-representation vote held last week, the AP reported that Gary Casteel, Tennessee-based regional director for the UAW,...