The difference is that without fiat currency, the government can't inflate it's currency to pay off the debts. At the very least it means that the population does not have the risk of their savings becoming worthless anymore, and it probably also disincentives the lender to give money for such purposes.
lottin|4 years ago
throwaway248329|4 years ago
Since the lender would know that they are not guaranteed to get their money back at the expense of the borrower country's population.