This story was co-published with The New Yorker and is not subject to our Creative Commons license. When Amazon opened its second fulfillment center in the Baltimore region, in 2018, most anyone driving to it from the city arrived via Dundalk Avenue, which took them past a yellow brick building that was constructed in 1952 to house Local 2609 and 2610 of the United Steelworkers and an adjacent building that opened after Local 2610 moved into its own space. By then, the buildings were mostly vacant, because the steel mill whose workers the union had represented had closed, in 2012, after a lon...