All other fiat currencies are similarly backed by a government that enjoys monopoly of legal force over some geographical area. That's why when governments die

All other fiat currencies are similarly backed by a government that enjoys monopoly of legal force over some geographical area. That's why when governments die (lost war, revolution) the value of their fiat goes to zero and only "money" with intrinsic value is accepted (gold, silver, gems, works of art, cigarettes). In 6000 years of recorded history money always either had intrinsic value or was backed by a strong guy.