Will russian red army destroy northern china or southern china?

China would kill Russia. Russia does have some pretty fancy stuff but their economy just isn't able to support a mive war. China, on the other hand, can support it. But I don't think a conflict between the two will happen for several decades but if one did, I would bet China would start it. Russia can't beat China in the Chinese homeland. But China would never want East Russia, aka Siberia, because there is nothing out there except maybe oil.