Here is a paradox. The world’s economy is steadily “decoupling” from the US. The extent of the effect can be overstated, but it is plain that a new engine of growth is rising, in China and India, and that the importance of the US thereby diminishes.

And yet there is no such decoupling of world markets. Quite the reverse. I have commented on this paradox before, but the panic-driven volatility of the past month has made it even more glaring.