That's an exaggeration. As of the 2014 per capita CO2 emissions in the US was 2.2 times Chinese (16.7mt vs 7.6).
And this gap is rapidly closing: Chinese per capita emissions are up 150% in the past 10 years while US are down 15%. China could easily exceed the US by this metric inside of a decade. Keep in mind that China already emits twice as much CO2 in total as the US.
I'm not sure those number take into account all the stuff that China is manufacturing for the US, that is not consumed locally. Yes, that CO2 is released in China but it's paid for by USD.
