People get weary, jaded, disillusioned: then they need some person or some thought to cheer them up, to reanimate them. The same is roughly true of whole countries. It is also true, to some degree, of the world itself. One’s joy at Obama’s nomination is not unsullied. There are five months to go before the presidential election, and it is by no means certain that he will be the successful candidate. Several times in recent decades thoughtful and imaginative Democratic candidates have been defeated by Republicans who, while not without some virtues, had the knack of understanding and playing upon ordinary people’s less noble instincts. And Obama, as a liberal person of colour, is obviously going to be the victim of strong attacks from those who are conservative and/or overtly or covertly racist.