So you can't explain how the concept of fiat is related to an IOU

But somehow I'm not surprised. People which can't explain some concept in simple terms typically just don't understand it themselves, as simple as that. Regarding the US dollar specifically, it may be illegal to destroy, deface, and alter it as well as counterfeit it or whatever, but there is no Federal law that would demand any private business to accept dollars as a means of payment or even trade with you. In fact, any such business can just choose not to give a damn fuck about you. As I told you, go and read what the US Treasury department says on this issue. If you come to disagree, you may want to post a link to such a law



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