Excellent question. Russia's involvement in the war (or lack there of), is a major plot point in Book Three. For now, here's how much I will reveal. Russia is NOT happy about the war in China, and did consider taking action early on. But the Jades took hold of China so rapidly that it became clear to Russia that they may have to accept the Jades as their new neighbor. For now Russia is officially neutral, but that may change....very, very soon. Also, consequently, the Russian arms industry has been selling hardware to both the Sino Union, the Jades, and India (who is part of the Allies).