A lot of people don't realize that Detroit is/was simply that, a boomtown... no different, really, than the silver or gold rush towns in the Old West. Detroit just did it on a larger scale and the boom lasted longer than most.
But the boom has been over for 35 years, at least, and all those people who left aren't coming back. Of course, "ghost town" is typically the successor to "boom town," and all you have to do is drive around the vast abandonment to see that evolution.
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