Starting next year, New Yorkers could join Silicon Valley workers and residents of cities like Phoenix, Pittsburgh, and Boston as players in a grand, growing, autonomous car experiment. General Motors, through its self-driving startup Cruise Automation, plans to put a fleet of autonomous Chevrolet Bolts onto the streets of lower Manhattan in early 2018. The company is already testing in San Francisco, and once it finalizes its application to run in New York (the governor loves the idea), expects to learn valuable lessons from the city's colorful chaos. Those will be important lessons, to be sure. But the move across the country raises a novel question.