You would buy USD after a crash ? I read some articles online that the US Government would switch to a new, gold backed currency. Sounded like a crackpot conspiracy though.
going back to gold backed currency will be economical suicide for any country within influence of western hegemony - instantly making them 3rd world countries in process. only china can have that status as biggest holder thanks to help of rothchilds. china will grow thanks to gold slowly changing its society with increased consumption.