Monday was a holiday in the US – Martin Luther King day. But Ben Bernanke was in the chairman’s office at the Federal Reserve, working through the holiday as he often does.

On his desk his Bloomberg, Reuters and Dow Jones terminals flashed red as selling in global equity markets spread from Asia to Europe. The US markets were closed, but US stock futures were still trading, and they too started to plunge. When US markets reopened on Tuesday it looked as though there would be a bloodbath.