Power of the Fed and China

I never knew that the Fed could cost China.

But here is the claim:

http://www.wsj.com/articles/chinas-central-bank-defends-position-after-yuan-hits-four-year-low-1450068419

How and what is the nature of this negative link, this news item does not explicate. But it is cited in the Wall St. Journal!

If it de-pegs from the US$, it means that China has autonomy over its currency.

And this will be a game changer.