What would happen if every US state had its own currency and we just converted it to US dollars to pay federal income tax, buy treasury bills, and for importing and exporting from the country?

All 50 state currencies could trade in currency pairs against each other and national currencies, and the state with the best monetary policy would win. This breaks the fiat currency monopoly and gives savers more options to maintain their buying power. What do you think? What are the dangers of this? — via @SJosephBurns

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