When Barack Obama won the US presidential election last year, one of the first papers prepared for him was a sober and prescient document drafted by the National Intelligence Council in Washington.

It was a forecast of how the world would look in 2025 and it did not pull any punches. It predicted a fundamental shift in relative wealth and economic power from west to east and an abrupt end to the “unipolar moment” the US had enjoyed since the end of the cold war in 1989. The world was in for a bumpy ride, it said, with competition for ever scarcer resources and a gradual transition to a new global power balance.