On the morning of July 12, 1917, roughly one in every eight people living in Bisbee put on a white armband, picked up a weapon, and helped round up their neighbors. It started with a copper miners’ strike. Workers had demanded safer conditions, better pay, an end to discrimination, and other changes. The mining companies refused, and by late June roughly half of Bisbee’s workforce had walked out. Then, before sunrise on July 12, about 2,000 men deputized by Cochise County Sheriff Harry Wheeler spread through Bisbee and nearby Warren. Wearing white armbands and carrying rifles and shotguns, they pulled men from homes and marched them to Warren Ballpark. There, workers were told they could leave if they rejected the union and went back to work. Hundreds agreed. More than 1,100 others were loaded into cattle cars and sent roughly 200 miles east through the desert with little water and no food. The train first reached Columbus, New Mexico, but the town refused to take them. So it c...