For what reason do you think this could happen? It is strange to me that anyone really thinks that the US is preserving world peace while sending military forces to attack sovereign countries causing hundreds of thousands of deaths in the name of some kind of democracy. For me personally, it doesn't matter what happens to the dollar, it should only be a problem for the US - people need to start thinking about how to strengthen their national currencies and look for alternatives.

Can Bitcoin be an alternative, can the Euro become the world's new reserve currency, or will something else take this place?