The auto industry was already weak back in 1980, yet you still think that is the source of Detroit's financial failure. It's laughable. The "white flight" was mostly done by 1967, hardly a factor, as black families poured in to fill the jobs that they left, so why did the local businesses dry up? The Top 10 employers in Detroit are not auto industry related - that is fact. Most of the Top 10 were created after the auto industry had already reduced its size, so they actually are creating new jobs in Detroit.
BTW - Up until 1962, most of Detroit's mayors were Republican. After 1962, all of them have been Democrats - every single one.
List of mayors of Detroit - Wikipedia, the free encyclopedia