NEW YORK — Sunday night I looked down from my 11th floor window on a Manhattan so empty that you could imagine the sidewalks had been created by some prior civilization.

A single car paused for a traffic light on Amsterdam Avenue. And then after the light changed, there was nothing else moving — no taxis, no buses and no delivery trucks — for as long as I looked.

Pedestrians too had totally vanished with the restaurants and bars shuttered. Every trip to an open drugstore, grocery or bodega has become a calculus in risk assessment. Is the item that I’m shopping for — a loaf of bread, a box of Kleenex, a pound of coffee — worth the risk of touching a door handle or stepping too close to a neighbor?

On the Upper West Side, the city that never sleeps has discovered its inner Rip Van Winkle.

After 9/11, New Yorkers huddled together in homes and restaurants out of shared loss and shared defiance. After the 2008 economic collapse, those who could afford to still shopped and spent in a determined effort to support imperiled neighborhood merchants.