For the first time in centuries, China now affects the global economy as much as it is affected by the global economy. In the years ahead, China is likely to account for between a third and half of growth in global incomes, trade and commodity demand, and its significance will only increase as its share of the world economy rises.

I returned last week from a trip to China with the dispiriting conclusion that the world lacks shared understandings regarding goals for the evolution of the Chinese economy, the objectives of China policy in the short and medium term, and the institutional structures needed to manage both co-operation and inevitable tensions. President Xi Jinping has rightly called for a “new form of great-power relationship”. But it must be embedded in, if not a new international economic architecture, then a substantially revised and updated one.

The first issue on which clarity is required is whether it is the objective of the US and the global community to see China succeed economically as a support for global prosperity and a driver of positive social and political change, or whether it is to contain and weaken the country economically, so it has less capacity to mount global threats. This is seen in Beijing as a live question, and is a matter of debate beyond the shrill rhetoric of protectionists and politicians.