The US has just had its weakest period of expansion since the 1950s. Consumption growth has been poor. Investment growth has been modest. Exports have been sluggish. But if you are at the top of the tree, the years since the last recession in 2001 has been a veritable golden age. Salaries for executives have rocketed and profits have soared, because the productivity gains from a growing economy have been disproportionately skewed towards capital.

For ordinary Americans, though, it has been a different story. Real wages have been growing slowly; at just 1.6% a year on average over the latest upswing, well down on the experience of earlier decades. Business, of course, needs consumers to carry on spending in order to make money, so a way had to be found to persuade households to do their patriotic duty. The method chosen was simple. Whip up a colossal housing bubble, convince consumers that it makes sense to borrow money against the rising value of their homes to supplement their meagre real wage growth and watch the profits roll in.