Apparently, before the Russo-Japanese war, Japan had been seeking to partition Northwest Asia between them, with Japan gaining Korea and Russia gaining Manchuria. Russia, seeing no reason to limit herself by making an agreement on spheres of influence with a weak and frankly non-white country, rebuffed these approaches.
As a result, Japan attacked Russia and won by the skin of her teeth and eventually ended up dominating both Korea and Manchuria. Russia meanwhile was humiliated and her revolutionary groups got a dress-rehearsal of how NOT to overthrow the Tsar. 12 years later, the experience would be put to good use when the Bolsheviks showed that they'd been awake during class.
So what happens if Russia is receptive to the Japanese approaches, and they agree to divide Korea and Manchuria up between them?
Personally, I wonder if they might end up becoming allies - apparently the Russians and the Japanese had rather good relations between the Russo-Japanese war and the Bolshevik Revolution - and wouldn't that make East Asia interesting!
fasquardon