Regarding foreign companies not selling back the resource, most the refining is going to have to be done internationally by foreign companies no matter who is responsible for taking the ore out of the ground and with no offtakes signed yet I don't see how it's even a valid argument yet.
I do see the concern with holding a foreign investor accountable for any long term problems, leaving a big mess, but your implying things that haven't happened yet. I guess I can dive into the two mining companies to see about there "track record" but I think if anyone is going to be held responsible for it's mining practices it's going to be happen here in the USA.