Those who were born in the US in the early 1940s, as I was, came of age in the most buoyant period of the 20th century. In the years between 1945 and 1960, personal income almost tripled. Philip Roth called it the greatest moment of ‘collective inebriation in American history’. After the Great Depression and two world wars, the middle classes were beginning to live America’s dream of prosperity; the less fortunate didn’t yet seem to be spoiling the charm of abundance.