International finance has long been based on the premise that what’s good for one country is good for the world, because increased trade benefits everyone. But according to a special report from Natixis, that may no longer be the case as economic growth moves from foreign trade to domestic services.
Looking at year-on-year GDP growth, the report finds that there has been a strong correlation between different countries and different regions. The correlations weren’t uniform – China and India were strongly correlated to each other but weakly correlated with the rest of the world – but there has been a clear, positive connection going back to at least the early 90s. For most people, this seems...

