Not sure where you got the Chinese 8% number, that seems to be the percent for USA imports on that page. For Chinese exports, the number is almost twice as much

Not sure where you got the Chinese 8% number, that seems to be the percent for USA imports on that page. For Chinese exports, the number is almost twice as much (14%). That means at a per-capita level if you account for manufacturing the average Chinese person emits 0.86x10.1=8.7 tons of CO2 while the average American emits 17.6x1.08=19 tons. Thus the American lifestyle causes 2.2x the pollution of the Chinese lifestyle. However, based on that article it seems the US has also decreased emissions even when adjusted for imports. It is still higher that almost everywhere else but offshoring isn’t the only cause of the decline.