Also curious on this one.

America is about 4% of the world's population and USD is the current global settlement rails for (the vast majority of) international trade. That trade isn't just Australia selling oil to Asia, but it's people buying 'stuff' off Amazon and having it shipped to them. So money, state control/issuance, and international activity all become entwined.

Doesn't explain why the US seems to have some extra-judicial authority to slap non-US citizens. Suspect there would have to be legal instruments contained within extradition treaties established as part of diplomatic relations with the US.