“Welfare” no longer exists as we once knew it, and ascribing Detroit’s present day problems to it is to bark up the wrong tree.
Detroit, despite fantastic infrastructure, no longer exists as an industrial town because, for the past thirty years or so, there has been every reason to build a factory anywhere but Detroit, or any other large, old, industrial city. Nobody is building atop those old crumbling steel mills in Pittsburgh, either. If you are foolish enough to buy a tract of industrial land in Detroit, you inherit any known, or potential, environmental concerns that may, or may not, be associated with that property. That’s why all the factories you see, that have been built over the last quarter century or better, are out on what used to be farm land, and generally as near to an interstate as possible. It would make more sense to be near a rail line, but all those places are within cities, so factories end up located away from water and rail transportation because of EPA regs and liability concerns.