According to official records, more than 150,000 people live in the city of Springfield, Massachusetts, but during a recent research trip there I didn’t see many of them. The downtown streets were almost deserted. It seemed as if every other store had closed down, and those that hadn’t had signs in their windows that read: “No hoodies, no loitering.” I kept glancing over my shoulder as I walked to the archives at the city museum, worried about who might be …