If Dresden and Hiroshima can be rebuilt, so can Detroit. It might be a good idea to populate the area with Germans or Japanese though if you expect to get any work done. Perhaps sell Belle Isle to the Taiwanese or Koreans?
You got that right. That current populace is 85% useless to do anything except union feather bed for city jobs, sell drugs on the corner, or shoot up. Almost all the politicians should long ago have been thrown in the slammer.
Lagos, Nigeria, has better prospects than Detroit as currently inhabited and structured.