IT’S 3 am, and the subway station has long since shut for the night. As I watch, a small group of people move along the platform in the eerie quiet, their anticipation palpable as they prepare to release a cloud of bacteria into the tunnels beneath the densely populated Boston area. Among them is a woman holding an array of translucent green nozzles, ready to release the agent. Her radio crackles to life: “The train has just left; we’re a go.”
