We change the zoning code so that it becomes legal to build a grocery store in those areas, then let the market do its work. Yes, we rebuild those cities: but

We change the zoning code so that it becomes legal to build a grocery store in those areas, then let the market do its work. Yes, we rebuild those cities: but that need not be done by force. We can simply relax the draconian Euclidean zoning rules which prohibit traditional mixed-use city building.