There is Detroit, Detroit and Detroit.

  1. Detroit the international metropolitan family of communities
  2. Detroit the city of Detroit
  3. Detroit the American Auto/Mobility Industry.

Number 1 Detroit is my Detroit and that Detroit forms the boundaries of what may be discussed in this forum. Detroit the city is the heart of that Detroit. Just about everybody in the world considers Detroit as number 1 Detroit. 8 Mile is just a movie to them.

I read recently that 60% of all automotive research is done in number 1 Detroit.

So yeah "Detroit [is] the hotbed of automotive technology".