The US really has no incentive to allow this to happen
Except that it has opened trade for US companies, and the reported numbers are often laughably misleading. Apple, for instance, nets almost all of the profits from an iPhone, yet in the trade balance an iPhone magically counts as a $1000 deficit with China. Further, it yields cheaper goods for Americans, and more efficiency.
The US was literally built on free trade, and sits right near the top because of it, so to read these nonsensical "but what if" arguments borders on parody. It is just a profound ignorance of history and even the most rudimentary of economics. It is one of those amazing things where people really, really don't understand what they have until they lose it.