With Zohran Mamdani’s ascent to Gracie Mansion, a democratic socialist is now chief executive for the largest municipal bureaucracy in the United States, meaning that he oversees the daily activities of roughly 300,000 employees. Most of these employees are what the political scientist Michael Lipsky called “street-level bureaucrats”: the teachers, firefighters, cops, bus drivers, and others whose jobs put them into direct and regular contact with civilians. But they also include the urban planners, economists, analysts, and administrators who operate behind the scenes and at the higher echelons of city government: the people who help write the city’s budget, study traffic patterns, and run grant and incentive programs.