I submit that a place with rampant starvation and the entire population is in the same straits will be such a place. Gold is only valuable when there is surplus. The US will probably not ever get to the first condition...but the worse off it gets the longer one will probably have to look to find a "buyer" for the gold. I do agree that it is likely the only thing that is going to retain value monetary wise, however.
Please, you really think something unique is going to appear now, that hasn’t in 5000 years of human history? Ther is ALWAYS someone willing to trade for gold. Always.