the reason is NIGGERS
(twitter.com)
Its because theyre mercenaries who literally could care less about what theyre "fighting" for so long as they get their paycheck and free college. The Chinese and North Koreans are either so far down the communist brainwashing hole the State has become a god worth dying for to them, or they are simply afraid their entire extended family will get shot if they dont march in unison. Either way, they actually *care* about defending the country they wear a uniform for.