This is assuming Tesla is buying their aluminum from overseas, which they aren't. They buy most of their aluminum, if not all, from Sapa in Portland, OR. I see they have been bought out in the last year by Hydro Extrusions. In any case, Sapa advertises that at least 50% of their aluminum provided to customers is aluminum they recycled themselves. With the tariff there will be even more pressure to recycle domestically and those companies that already do it will be in a position to scale up their existing operations. My massage therapist's husband is an engineer at Sapa. I believe she said Tesla is one of their biggest customers. And Sapa may be getting some supplies from overseas. I don't know where Tesla is sourcing the steel for the Model 3 (and the steel that goes into the S/X, there is some), but one of the cost savings aims for the Model 3 was to keep supply lines from raw materials to final production as short as possible. I wouldn't be surprised if they are sourcing steel from a steel recycler in the west somewhere.