As I stepped onto the sidewalk, my attention was briefly caught by a man and a woman who had just gotten out of a parked car and who were glancing up and down the street as if searching for something. Call it an ex-cop’s instincts, but they struck me as suspicious. I scanned their faces: tanned skin, dark hair, a slight Amerind cast to their features. They looked Hispanic, like everyone else in this neighborhood. I guessed their age as early twenties.