A foreign trade advocate travelling to Japan 200 years ago would have had to deliver his message from the artificial island Dejima in Nagasaki bay, where the merchants allowed to trade with the country were locked up at night lest they infect the Japanese with their new-fangled ideas.

At least some things have improved. Peter Mandelson, European Union trade commissioner, was permitted to travel to Tokyo on Monday to deliver a lecture on what he labelled Japan’s closed environment to foreign direct investment.