In many ways, it’s like a ghost town. It’s eerily quiet. Driving around in the middle of the afternoon, in a city that once was among the most productive on the planet, you see very little traffic, minimal commercial activity, hardly any pedestrians.

What you’ll see are endless acres of urban ruin, block after block and mile after mile of empty and rotting office buildings, storefronts, hotels, apartment buildings and private homes. It’s a scene of devastation and disintegration that stuns the mind, a major American city that still is home to 900,0000 people but which looks at times like a cross between postwar Berlin and the ruin of an ancient civilization.

Detroit was the arsenal of democracy in World War II and the incubator of the American middle class. It was the city that taught mass production to the rest of the world. It was a place that made cars, trucks and other tangible products, not derivatives. And it was the architect of the quintessentially American idea of putting people to work and paying them a decent wage. It’s frightening to think seriously about what we’ve allowed to happen to this city and what is now happening to the middle class and the American economy as a whole.

I was in Detroit with Harley Shaiken, a professor at the University of California, Berkeley, who specializes in labor issues. He grew up in Detroit and his love for the city and its people are palpable, as is his grief for the horrors the city has endured.

The popular narrative of what happened to Detroit contains a great deal of truth but its focus is too narrow to account for the astonishing decline of this former industrial colossus. Yes, there were the riots of 1967, and white flight; and political leadership that was not just shortsighted but at times embarrassingly incompetent and corrupt. And, yes, the auto industry was a case study in self-destruction.

But as Mr. Shaiken points out, Detroit was still viable enough for the Republican Party to hold its convention here in 1980, when it nominated Ronald Reagan. And it was not the riots, but the devastating recession of the early ’80s that really knocked the city senseless. “That’s when the place really cracked,” said Mr. Shaiken, “and that was about aggressive globalization and the lack of an industrial policy, not the riots.”