Hui Muslims are a recognized ethnic minority, and have a history of problems and genocides against them under some Chinese dynasties, specially Qing (Ming was founded by a Hui as Legend goes and Yuan was friendly to Hui who were given high positions, 2nd tier after Mongols, as many were descended from fellow Central Asians). But they have been peaceful since wwII, as far as I know, except for occasional flare ups with majority Han, but it is heard more often in Hui areas like Ninxia, not Shandong, which is close to Korean peninsula.
China has a major product quality problem, cannot be denied. Need much improvement and will happen in due time, hopefully.
Korean copying Japanese has been a problem. Korea being a vassal nation of Chinese empire took its toll, the Japanese colonial rule did not help much either, although many claim it "modernized" Korea, just like the British "modernized" British India. But the people who had to live under colonial rule, of course disagree with that narrative.
Korea has been a victim nation for a very long time. Hopefully both Korea and Japan can look past their mutual problems and work together for a better future of Asia. If they put their mind to it, they can easily handle the Chinese threat of domination in a creative way, and reduce their dependence on the West for security.
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. I will post this youtube. 
And other trolls quickly jump into this talking about censorship without even bothering to investigate. 
