American cities are shaped by the accumulation of many small choices across time: to put a park here, to lay a sewer there, to rezone this commercial strip or redesign that roadway.

But every now and then, a momentous decision is made — to reverse the Chicago River, to construct the Dallas-Fort Worth airport, to move a highway underground in Boston’s Big Dig. And it changes what’s possible for years to come, altering a city’s growth, its economic prospects or the very nature of its public space.

Congestion pricing could have been such a turning point in New York, according to proponents for whom the policy promised not just new revenue for mass transit, but also a fundamentally novel approach to reining in the cost of cars in an American city center.

Gov. Kathy Hochul’s decision to halt it may be remembered as a turning point, too.

“Manhattan south of 60th Street is essentially an invention for creating prosperity for the human race,” said Tom Wright, the chief executive of the nonprofit Regional Plan Association, which has pushed for congestion pricing. “It’s an engine of jobs and creativity, and what it does is it employs millions of people. And it grows.”