Bingo! Now analyze your own paragraph. Russia and China are potential threats to the US. This means, the US has to side with one to deter the other. This means, either US-Russia alliance against China, or China-US alliance to keep Russians in check. I think the US will go with the US-China alliance because it's more sensible. By joining hands with the Chinese, the US will make Russia spend more on its defense because an US-China alliance means Russia spending a lot of $$ on deploying troops in Siberia. Iso Ji I do not agree with above statement. So far I have known, I believe China and Russia will maintain strategic stability with each other mainly to counter US influence in Central Asia, that may not be in the form the counter attack but by posing potential challenge. Sino-Russian relation is more stable then ever before in the history. Chinese perception of Russia is: Russia is and will remain next to super power with a major impact on regional and world affairs but will not seek hegemony. Russia should maintain territorial integrity with China (regarding your Siberia issue) in order keep its border inviolate with other former Soviet's states. Secondly it is not up to US whether to go with Russia or with China. It will totally depend how latter countries observe the current US's maneuvers in Mid-East region. IF Sino-Russia pact has seriously deters not to seek world hegemony- I don't think they will take this granted from US side. Here you say: From the US perspective it's presence in the Middle East and Central Asia is to keep both China and Russia in check. Bingo If so then why it is not possible for Sino-Russian to cooperate each other to counter check on US? If you have known, US presence is merely to check Russia and China, most obviously Russian and Chinese have also known about that? But what will happen if and when the US leaves the region? The Russians will immediately take over, which will pose a security threat to China. I do not agree. Russians are still not ready to take over anything or anybody. The picture is broader than what it was during Cold War. Current Russia itself is facing multitude domestic problems along with conflict in Chechnya. It has to keep well alert from anti- Russian (former soviet's) states. Under such circumstances, by no means Russia will ever ignite conflicts around that region. And China do clearly understand this. The US knows it cannot stop Russia so it won't make much noise when Japan pumps money to Russia. I do agree to some extend and I am not surprise to know Japan pumping money to Russia. Russia, nonetheless is a dealer - exactly they are doing what they are suppose to do- Guns-for-Butter. And why should American be reluctant with such deal? But if you were talking about Japan -Russia ties, I would say relation is more volatile than that Sino-Relations. Their (Japan-Russia) territorial issue is still as hot as red iron and they will remain headstrong for sake of those four islands. Conclusion: Sino-Russian power is getting stronger and further will be strongest if US do not change its imperialistic attitude.