The next president is never going to come out with such a statement, not in the next century at least. The US dollar is the worlds reserve currency, meaning a lot of other countries trust it as a relatively stable asset in an increasingly turbulent world - they're happy to convert their own cash, at whatever the prevailing rate is at, into dollars and even have it slowly inflated away by "quantitative easing" (aka money printing). Having control of the reserve currency of the world is an unbelievable gift to America and gives them control over all sorts of financial levers that other countries will never have. No sane government official in the US would ever suggest such  thing, as best it might be begrudgingly allowed as an asset but even then - it simply does not have anywhere near the transaction power needed for everything taking place each day even in a small country.