Like many powerful currencies in the past, USD may fall to ground too, my question is will that effect BTC value? Or is it independent of all other real world or non digital currencies of the world?
Well last failed currency would be Germany and Japan after WWII .
I wont count South Vietnam or a few other smaller countries.
So if USD fails it would be most like due to a terrible event. War or comet strike.
I dont see a fail in the currency but if it does happen a new major fiat would be needed maybe btc would whale