The story begins in the heart of New York City, snarled in intolerable traffic.

The problem has worsened over the years as New York filled up with cars, taxis, buses, and trucks, and traffic has now slowed to a crawl. Tempers are frayed. Taxis blame private cars for the problems. Private cars blame taxis. All feel overpowered by the growing number and size of trucks, while the truckers themselves become more frustrated and aggressive in their attempts to meet delivery deadlines: The heavier the traffic, the ruder the truck drivers became. At busy intersections, they never let anyone else turn first. If anyone tried to, a truck driver had only to gun his engine and keep on coming. Few automobile drivers cared to argue with a twelve-ton truck, even when they were in the right. Even the taxi drivers began to lose their confidence.

Throughout all of this...