I assume that David’s title was partly tongue-in-cheek. Anyway, consider what Kay Hymowitz writes.

Between 1950 and 1980, Brooklyn lost half a million residents. And the blue-collar decline continues in the new millennium, with the borough losing more than 9,000 manufacturing jobs between 2005 and 2010.

Read the whole thing. It tells the story for one city that I tell for the whole country. After WWII, we become a nation of clerks. Now even the clerks are losing their jobs to machines. Hymowitz writes,

For all their energy and creativity, Brooklyn’s young entrepreneurs tend to have few employees, and they’re not likely to be hiring large numbers in the future.

Again, read the whole thing.