That was spot on.
Superman: Don't worry, Lois, I've got you.
Lois Lane: You've got me--who's got you?!
After Nixon Shock, the US was still able to borrow prestige for the USD from a number of angles, the strongest of which was the dollar's former reputation and strength when it was backed by gold -- the closest thing to a 'stable' currency the world had already in wide circulation.
China has currency problems of its own with the Yuan, as the RMB is every bit an irredeemable fiat currency as the USD. Worse yet, the Yuan got its strength primarily from the Fed dollar through its trade with the US. In the end, they are all deliberately inflated fiat currencies in a bunch of fiat debt-money regimes.
Even so, China has been pushing for some time to prop up the RMB in the eyes of the world, in the hopes of getting it into the PetroYuan catbird seat, if nothing for its inflationary-hiding/misery exporting benefits, as demand for that currency is increased. Even selling off US securities and raising its peg against the dollar can some the illusion that the Yuan is 'standing on its own'. Most of the players involved aren't that stupid, and realize this, but while China has been desperately trying to make the RMB appear conservatively managed and somewhat well-behaved, all the Fed's rounds of Quantitative Easing, especially this last one, assures that the Yuan at least looks like a much lesser of two evils. And what has this insane world of ours been about, if not kicking the can down the road a little longer?
But there is much more to it than that. Whole economies are so intertwined with interdependency on trade with the US that a tsunami of increasingly worthless Fed-inflated dollars returning to the US could not only easily trigger hyperinflation in the States (a total loss of confidence in the Fed dollar at home), it could just as easily send the entire world into a massive, catastrophic depression.
Oddly enough, any transition using multiple competing fiat petro-currencies would serve as a natural check and balance against all of them. The US economy would still drown in its own worthless currency, but instead simply wiped out in a tsunami, it might be more like Chinese water torture. Economic water-boarding, as it were, as even our hyperinflation is 'managed' externally.