I think it will be many years before we reach American level of economic output, in nominal terms.
Unless the dollar is no longer the world's reserve currency, then nominal GDP will look the same as PPP.
It depends on how the appreciation of the yuan is going to be managed. It can come quickly or not, depending on what the PBOC wants.
But of course none of that matters - remember the United States is psychopathic and full of people who want to bring about the end of the world. It doesn't matter if a deranged maniac is half your weight, he can still plunge a dagger into your heart while you're not looking.