When Xi Jinping arrives in Washington this month for his first state visit to the US, the pomp and ceremony alone will have made the trip worth his while. All the Chinese president’s men attach great importance to 21-gun salutes, state dinners and other such symbols.

But for US multinational corporations, which tend to value substance over style, the boiler rooms at the Office of the US Trade Representative and China’s commerce ministry are the site of the really important action. Those mundane settings are where a historic breakthrough in Sino-US commercial relations may be forged — or fall apart — over the coming months.

The bilateral investment treaty, or BIT, being negotiated by the world’s two largest economies has the potential to reshape China’s operating environment for foreign companies, much as the country’s entry into the World Trade Organisation did in 2001. It will also provide the best litmus test of the bold reforms outlined by Mr Xi two years ago, when the ruling Chinese Communist party said that the market should play a “decisive” role in allocating resources.