When he last visited China two years ago, US Vice-President Joe Biden found time to have lunch at a Beijing snack shop and even went on a feel- good trip to Sichuan with his then Chinese counterpart Xi Jinping.
The mood in China was far less welcoming when Mr Biden visited again on Wednesday, in the midst of rising tension over China's new air zone.
Mr Biden was reportedly sombre after emerging from a meeting with Chinese President Xi Jinping that went longer than scheduled. But in their public comments, both refrained from letting the tension show.
Mr Xi highlighted the need for closer bilateral cooperation in the light of the profound and complex changes in the international and regional landscape, citing the "in-depth readjustment" of the global economy and how "regional hot spot issues keep cropping up".
"The world, as a whole, is not tranquil. To strengthen cooperation and dialogue is the only right choice facing both our countries," said Mr Xi.
In response, Mr Biden said the approach to their bilateral ties has to be based on trust and requires "a positive notion about the motive of one another". "If we get this relationship right with a genuine new model, the possibilities are limitless," he said.
Mr Biden did not elaborate, but the two powers have been exchanging sharp words in recent days over China's air defence identification zone (ADIZ) in the East China Sea launched on Nov 23, which overlaps with those of its neighbours.