Russia and China, eager to gain important and useful friends, have found new solace in each other's arms. Presidents Vladimir Putin and Jiang Zemin spent a busy day together in Beijing this week, signing several agreements and declaring themselves opposed to letting the Americans dominate global affairs. Specifically, they warned jointly against US plans for national and regional missile defence systems, and against letting Taiwan become independent. In brief, they put new life into an existing friendship between the world's biggest and most populous nations, which don't always have much in common. There are advantages for both in doing so, and even some for the region. But while this raises questions about creating a powerful and possibly fearsome new alliance, nothing that dramatic seems likely. By joining forces, Moscow and Beijing do increase pressure on Washington to scrap or curtail its missile plans. The Chinese fear the small US national defence system under consideration might expand to nullify their own rocket forces, reducing sharply their military influence. They also fear the US might establish a local defence system someday on Taiwan, countering the force - 300 missiles and growing by 50 per year - that China is establishing across the strait. Russia has less to fear. No conceivable US defence system could offset its extensive rocket forces, and it has no direct interest in Taiwan's fate. But Mr Putin does want to prevent new American spending which might trigger another arms race which the Russians cannot afford. So he is quite willing to support some Chinese views in hopes of leveraging Russia's own world influence. Given past tensions, anything that promotes peace and commerce along the Russian-Chinese border is good for Asia. The entire neighbourhood will benefit from such calming influences. But this renewed friendship has distinct limits. Trade between them is small and - some weapons aside - has limited prospects. It will probably reach only one-third of its 2000 goal of US$20 billion. And, like it or not, the US remains more important to both nations for economic and political reasons than they will be to each other for many years to come.