Real wealth can only be measured in the few things that actually matter, namely consumable natural resources. As far as those go, America's FIAT currency still buys the lions share of it.
American debt doesn't seem to matter all that much, as the entire world is still on their knees trying to blow America for the chance to get a little piece of what we have. So, hate America all you want, but your facts are simply wrong. American buying power is as strong as ever.
As for waiting for America to die off, I would not be so eager. Do you really think the American people are ones to go quietly into that goodnight? When America goes down we are taking the whole world with us in a fiery orgy of destruction.