In the balmy days before the subprime crisis, “decoupling” suggested emerging markets would be safe from a developed world storm. It turned out the theory was wrong. That has not stopped a new round of decoupling, this time between Europe and the US.

European banks have plummeted. But strip financials out of the index, and eurozone companies still did far worse than their US cousins. From their peaks eurozone non-financial shares are down 31 per cent, while US non-financials fell only 14 per cent.

There are two ways this could be justified. The conjoined banking-sovereign debt problems in Europe are already forcing its banks to cut back lending. Banks are having trouble securing short-term funding; two banks had to turn to the European Central Bank for dollars again this week. That is likely to push the eurozone towards recession more quickly than the US.