A meeting of the two largest economic powers

CHINESE President Xi Jinping is visiting the US and meeting US President Barack Obama in the White House this week. They met in Beijing last November when they agreed on stronger voluntary efforts against atmospheric pollution - hopes again run high for new agreements to be made. Of course there will be a public agenda, but their many aides will hold wide discussions, some will focus on trade and on the Trans-Pacific Trade Agreement.

World trade volumes faltered after the financial crash of seven years ago but there are signs of renewed optimism as earlier initiatives come into operation. The expansion of the Suez and the Panama canals are virtually complete and will allow the largest of ships to pass through.…