Are you clueless you sad racist fuck. Detroit (and many other American industrial cities) went to shit soon after World War II. Much of happened in Detroit alone that had to do with the death of Henry Ford who was known to believe in the welfare capitalism and his failed social engineering of his employees much of which he borrowed from Fredrick Taylor. That legacy lives on today. It had/has little to do with ethnicity. So, before opening that festering gob of yours again take 15 minutes and watch this and learn something about worker exploitation and why the rich get richer and dumb fucks like you only become dumber:
0:37 to about 1:48-ish explains what happened in places like Detroit. You moron.