Notes as money is bizarre share-cropping, and USA people would be reasonable to advocate for coins in larger denominations like 10 50 and 500 to avoid borrowing notes into existence.
https://www.usmint.gov/news/inside-the-mint/how-coins-are-ma...
"Federal Reserve Banks buy coins from the Mint at face value."
Even if it's not recorded as such, money is always a liability to its issuer, otherwise there would be no point issuing it.
Not in USA. US coins are fiat without a liability. This leads to people every few years thinking they discovered that coins are just fiat and then recycling the idea of minting some $1 trillion coins and paying off the federal debt. It is technically possible, there would be no debt for the coin issuance, and would likely lead to nobody willing to purchase future USA debt issuances.
https://www.investopedia.com/terms/t/trillion-dollar-coin.as...
Really bizarre are the gift shops at the US Treasury's Bureau of Engraving and Printing where they have tours to watch the printing presses. They sell to tourists uncut sheets of dollars that they print. But they first buy the sheets at face value plus the printing costs from 'federal reserve' who bought the sheets at pennies per _sheet_ that Treasury just printed.
https://www.federalreserve.gov/aboutthefed/chapter-5-federal...
"When purchasing the notes, the BEP authorizes the Reserve Banks to charge Treasury's general account for the face value of the notes plus the cost of printing."
No, though prove me wrong and show us the coin liabilities on USA balance sheet somewhere.
In practice a coin is a token that represents a liability at the Fed much like a deposit. That token can be used to claim an actual deposit at the Fed (by agents, not little people, obviously).
I'm not aware of a law that requires a coin be bought by the fed at face value. It just seems to be the historical norm. If you're aware of such a requirement please let me know.
In summary, the coins are not the "money", they're just tokens that for historical reasons the fed buys from the treasury at face value and can record at face value in their balance sheet. It could in principle just as easily be the case the fed is not required to balance with anything from the treasury (e.g. not T-bills) against new money creation - they're just forced to hand over the deposits to the control of the treasury. The net effect would be exactly like the coin case (hence the trillion dollar coin nonsense).
National debt is a primary tool to support growth.
Breaking glass windows also increases growth (or GDP) because it forces spending to replace the broken windows. Similar GDP increase when USA builds missiles to blow up bridges (over there somewhere) and later provides funds to US contractors to rebuild those bridges. GDP number go up, along with debt and interest costs.
I've been in favor of abolishing the minting of physical US pennies, but I suppose this is one argument against it: other countries that use the dollar might actually find pennies to be useful.