Rural America has long been where the rest of the country sends what it doesn’t want nearby: prisons, power plants, landfills. These days, two more intrusions have been added to the list: immigrant detention centers and data centers. In December, Larry Bender, the supervisor of Tremont Township in Schuylkill County, Pa., learned to his great surprise that the federal government had purchased the largest commercial property in the township: a 1.3-million-square-foot warehouse that had been a Big Lots distribution center. It would now be used for immigrant detention. Tremont is home to about 300 people. The facility was designated for...