What a difference an “and” makes. The US-China Strategic Economic Dialogue (SED), a twice-yearly bilateral encounter centred on economic issues, has morphed under President Barack Obama into the broader Strategic and Economic Dialogue (S&ED). For those with a grammatical bent, the addition of a conjunction transforms the word “strategic” from an adjective describing the economic dialogue into a portmanteau adjective describing anything Hillary Clinton damn well wants.

The upshot of US inter-agency rivalry is that Mrs Clinton's state department joins Tim Geithner's Treasury at the heart of the conversation with Beijing. That is no bad thing. It has broadened the agenda from what Hank Paulson, Mr Geithner's predecessor, originally conceived in 2006 as a narrowly economic forum. Now that the state department has muscled in, climate change, North Korea and any other issue of global or bilateral import have joined US deficits, financial sector reform and the renminbi as potential subjects for discussion.

Widening the agenda of talks, the latest round of which wrapped up in Washington on Tuesday, makes sense. The Sino-US relationship is evolving fast. Mr Obama's China policy builds on foundations laid by his predecessor. For a president who promised change, one area of constancy with George W. Bush's White House has been the posture towards Beijing. That was one of the few things his predecessor was judged to have got about right. Unlike Mr Bush, or Bill Clinton before him, President Obama has not had to backpedal from initial hostility towards China towards a more accommodating stance.