So with speculation that the majority of North Koreas capital coming from BTC, who thinks that China banning ICO's was a step to curbing North Koreas power?
I do not think so since China really do not care what the United States think about them. If China do care they would Probably abandoned the Islands that they occupied in the Philippines sea.
The most probable cause of China's policy is regulation. The whole world knows that China was once a communist county. They would like everything to be regulated and since they were unable to regulate the coins they created this policy. But most likely once they figure out how to regulate ICO and crypto trading they will lift the Ban.