Not before time, the new spirit of brattishness which seems to have infected adults, particularly those in public life, has been receiving attention here and in America.
Responding to a survey which purported to reveal that in some countries women are now brainier than men, Janet Street-Porter suggested that modern men have one or two maturity issues. "Have you noticed how many of them are morphing into big babies?" she asks. "They dress like oversized toddlers. They read comics. They can't function without their toys… In short, many men have retreated into a pre-teen world, where they don't have to spend much time dealing with the nasty real world."
Some might see these grand generalisations as an instant refutation of the conclusions of the intelligence survey, but surely Janet is at least 50 per cent right – the other 50 per cent being provided by women, who are not noticeably more grown-up than men.
Immaturity becomes more than merely annoying when it is evident in the people who are meant to be in charge of things. Watching bankers as they appear before a select committee, or ministers and press grandees giving evidence to Leveson, or hearing quangocrats and academics interviewed on the Today programme, one is nigglingly aware of something new and unusual in the way these people see the world. They are never quite serious. Even when imitating seriousness (take a pearly-toothed bow, Mr Diamond), they are larking about. Nothing really matters that much.
Last week, in an important but widely misunderstood essay called "Why our elites stink", the New York Times columnist David Brooks argued that the emphasis on youth and brains in today's meritocracy had come at a price. Today's bosses lacked "the self-conscious leadership ethic" which the old class-based elite once passed on from one generation to the next.
The Libor scandal had shown that bankers were brats. In fact, Brooks argues, those in power have trouble even recognising that they are part of a privileged elite. "Everybody thinks they are countercultural rebels, insurgents against the true establishment, which is always somewhere else."
The connection with hippies and the counterculture of 40 or so years ago is odd, but interesting. Then, alternative leaders like Richard Neville spread the gospel of play power: it was through having fun, making love and taking nothing seriously that a gentle revolution would be wrought. The hippies played while the straight establishment looked on disapprovingly.
Now it is the other way around. People who believe that Western capitalism is fundamentally wrong – the Occupy activists and others – tend to be severe and humourless while those in positions of power gad about merrily, lacking any obvious sense of a wider responsibility, or what Brooks calls "a stewardship mentality".
Perhaps it was inevitable that, when PR ethics took over politics and business a few years back, the idea would wither that political and business leaders owed it to society to take what they were doing seriously. For all their flaws, the suited worthies of the past were at least grown-up. Because the culture is also in love with playfulness, politicians who are deemed to be guilty of the great modern sin of taking themselves too seriously (William Hague, Harriet Harman, Vince Cable, David Willetts) are mocked for being solemn, for lacking charisma.
Such is the sea change in public life that when, at one of the televised inquiries which have become part of ours news diet recently, a civil servant is interviewed and gives considered, sincere, slightly dull replies, it is as if a teacher has suddenly entered a riotous playground – both reassuring and slightly embarrassing.
Our elites stink because they are run by people who prefer to think of themselves as mavericks rather than members of the establishment. In their cheerfully irresponsible world, what matters are the brattish pleasures of winning, being popular, bullying the wimps and, above all, getting lots of sweets.
A lesson we could all usefully learn from Nature
Visitors arriving on these shores for the great Olympic bonanza will no doubt be looking around for signs of the miserabilism for which the British are internationally famous.
They need search no further than a report this week from that normally sensible institution, The National Trust. The rain and cold of this summer has had an appalling effect on wildlife, the Trust says. Only slugs, snails and midges have benefited. There will be extinctions among birds, bats and butterflies in some areas. The word "apocalyptic" has been used.
The problem with this tendency towards anguish and anxiety is that it affects the way we all view the natural world. The sight of a barn owl in the daytime provokes worries that it was unable to hunt at night. Dead hedgehogs on the roads will be seen as tragic news for the Tiggywinkles rather than evidence that they may not be doing as badly as we thought.
This summer is not an apocalypse. It is weather. Nature knows how to deal with it. We could usefully learn the same lesson.