“The practice of street photography has a long tradition in the United States, with documentary and artistic strains, in big cities and small towns. Photographers usually must obtain permission to photograph on private property — including restaurants and hotel lobbies — but the freedom to photograph in public has long been taken for granted. Remarkably, this was the first case to directly challenge that right. Had it succeeded, “Subway Passenger, New York City,” 1941, along with a vast number of other famous images taken on the sly, might no longer be able to be published or sold.”