Mr Wilhelm is inviting everybody to join a zero-sum world of beggar-my-neighbour policies in which every country tries to grab market share from the rest.

We seem to be following the same path, and in a beggar-thy-neighbor world any country that does not participate in retaliatory policies will suffer.

And there are concerns that China may allow the yuan to depreciate to help its exporters-with worrying echoes of the beggar-thy-neighbour policies that exacerbated the Depression.