> There isn't a single country in the world today where you can't spend a US dollar. The strongest argument I think I can construe from your statement is that

> There isn't a single country in the world today where you can't spend a US dollar. The strongest argument I think I can construe from your statement is that every country has at least one place where you can spend a US dollar but I don't think that's very useful. If you bring a 20 USD bill to Europe, head to the center of a major city and try to spend it, I think you'll have a pretty hard time handing it to a shopkeeper. You'll have trouble spending it at all save for exchanging it for the local currency and handing that to a shopkeeper.