Chicago and New York both have white pluralities and huge sections of both cities are very wealthy and very safe. Detroit is essentially one big ghetto.
Well, the original poster could have been more specific than "majority-minority." All major cities outside of maybe Phoenix are majority-minority or soon will be.
There are issues to be discussed here but the original poster was nibbling around the edges.
I know all three cities. I've lived in the NY and Detroit metro areas and have spent a good amount of time in Chicago.
For the most part, Chicago and New York have been pretty blessed with the mayors they've had. Sure, the Daleys and their henchmen have run Chicago like their personal kingdom, but Chicago's mayors have always loved their city. Chicago's always been "The City That Works." I can live with a little bit of greased palms and corruption if the streets are safe, potholes are fixed and garbage gets picked up. With a few exceptions, New Yorks's mayors have been cut from the same cloth.
Detroit, on the other hand, went through 20 years of Mayor Coleman Young, who cared nothing about Detroit as a city. He and his cronies only wanted to get their piece of the pie, and to hell with Detroit and everyone else in it. The city's falling apart? Well, just blame Whitey.