Earlier quoted context omitted.
This is replicated all over the rust belt. One of the saddest portrayals of this is the photo essay, The Ruins of Detroit[1]. These once mighty economic engines have been silenced: manufacturing, coal, etc. What happens next is that the people who depend upon these industries to make a living, and live ... do less well of a job of this. Some argue that unions would help (they wouldn't), or anti-globalism would stop f…
Oakland county just to the north of Detroit is one of the wealthiest (93/3100 by per capital income), most educated counties (44% have bachelors or higher; San Francisco is 54%) in the country. Washtenaw County, just to the west, is also high on both of those measures. Wayne County (where Detroit is located) is middle of the pack on those measures, not at the bottom.
Washtenaw County is likely up there because of the University of Michigan in Ann Arbor. The biggest hospital by gross revenue, third biggest by bed count is here, as are a whole bunch of research parks related to the automotive industry.