Hank Paulson, Treasury secretary, must strike a delicate balance when he leads a high-level team to Beijing this week for the first US "strategic economic dialogue" with China. He has repeatedly warned against expecting rapid results. Yet if the bi-annual talks are to have time to bear fruit, he must be able soon to show evidence of solid progress to a US Congress whose patience with Beijing is wearing thin.

Mr Paulson's caution is understandable. His proposed agenda is vast and complex, spanning many of the most difficult domestic policy challenges confronting China, from monetary policy to the environment. Furthermore, China's leadership is currently far from united about the urgency of tackling them and increasingly hesitant about undertaking the politically painful reforms they are bound to entail.