Hi Corky. In such a scenario, I imagine Russia would deploy nukes against China. The Russian Far East Oblast has a population of 8 million people, a small sacrifice for the cynical Kremlin to save Mother Russia. The more interesting scenario would be China launching a surprise attack against North Korea and defanging Kim Jong-un once and for all. To Beijing, Pyongyang is a nuclear tumor causing instability. And Kim Jong-un is readying his daughter to be his successor, which China sees. How many WMDs will North Korea have accumulated when she takes over in a few decades?