Julia Vicente always walked the same route home from visiting her friend. She’d traverse about a mile of Shiprock, a town on the Navajo Nation in New Mexico’s northwestern corner, along a dirt road through a neighborhood, bordered by hills and an irrigation canal on one side and a busy highway on the other. She’d turn onto a well-worn path that cuts around and through a few fields before coming out behind a gas station. She’d cross the highway. From there, her house was straight down a tree-lined street.