The US and China are locked in a teetering dance, each grudgingly matching one another's first steps. This week, in a speech at the start of his visit to Beijing, Tim Geithner, US Treasury secretary, set out a plan for how this relationship can develop into a more graceful arrangement. Mending the world economy, however, must go beyond mere bilateral talks.

Mr Geithner's speech was geared towards both US and Chinese audiences. He sent a reassuring message to China, the largest buyer of US government debt, about his plans to cut the fiscal deficit. By setting out his stall first, the Treasury secretary managed to avoid the impression of being an incorrigible wastrel, summoned to see his suspicious bank manager.

Mr Geithner also noted that China needed to change its economic model. Beijing does need to move away from its export-orientation. But, by acknowledging that the US is equally responsible for the world's economic imbalances, he made his case without upsetting his hosts. This was no mean feat.