Maybe because the United States is the 'least bad' super power. It has a far from clean record but at least it isn't currently engaged in a genocide.

The US also has one of the most solid judicial systems in the world. In fact, the Supreme Court and other courts regularly challenge and restrict the actions of the current administration. If you go to court, chances are you're going to get a fair trial.

If you are a Westerner and go to court in China, you will lose. It's that simple.

If the United States falls and China attaches itself to the power vacuum that ensues, the entire world will be worse off.