It's also worth noting that the other resource a nation can require payment in it's own currency for is land - i.e. for both farming and mining purposes, both o

It's also worth noting that the other resource a nation can require payment in it's own currency for is land - i.e. for both farming and mining purposes, both of which attract taxes denominated in local currency. You open say, a hard rock mine somewhere in the US, you have to get mining permits to do so which are paid in...local currency.