I'm not sure why it is super important to protect jobs only in Detroit and Ohio.
Have to build where people will continue to support the projects through the political cycles. Tangentially, consider where folks will keep migrating to as rural America continues to hollow out. Most of this work is going to be automated in the future (as China does today), so the labor force available is less relevant (versus climate risk and clean energy availability).
China, for comparison, has the capacity to build ~20M EVs per year, and satisfy current total global EV demand (they are export capacity constrained). Will the US ever be able to build more than a few million units a year? Probably not, on current trajectories.
https://newrepublic.com/article/195350/republicans-rejoicing...
https://news.ycombinator.com/item?id=48586250 (citations)
https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu... (my comments on Rural America decline)
(think in systems, "demographics is destiny")