We live in one of the wealthiest, most technologically advanced nations on earth. We've had 60 years of peace and prosperity with free education and medical services for all.
Our homes are crammed with labour-saving devices and electronic entertainment that previous generations couldn't even dream of. Surely our children should be growing happier every year?
Well, no. According to figures released last month, one in ten now suffers from a clinically-recognised mental health problem, and earlier this year a UNICEF report on "childhood well-being" found that out of 21 nations across the developed world, British children are the unhappiest...
We've come to believe that 21st century children are different from children in the past - that they can get by with less parental time and attention, skip stages in their development and cope with pressures and emotional burdens children shouldn't have to cope with.
The brutal truth is that they can't. Life may have changed enormously over the past few decades, but the human brain evolves much more slowly - in fact, it hasn't changed since Cro-Magnon times.
All babies are born as little Stone Age babies, and it's up to their parents - supported by their wider community - to help them towards maturity, gradually equipping them with the inner strength, skills and knowledge they need to live in a complex technological culture...
The "obesity explosion" of recent years shows that society - parents, manufacturers, marketers, even the schools that fed children turkey twizzlers - lost sight of the importance of wholesome food in recent decades.
As for shelter, we've confused that with over-protection, keeping children wrapped in cotton wool to keep them "safe", and thus denying them essential opportunities to learn through real-life experience - actually getting out on their bikes and breathing fresh air.
And in a 24/7 culture, where sleep has been sidelined as electronic entertainment fizzes on throughout the night, children may well be getting less sleep than at any time in human history.
Another essential childhood need is the emotional stability that comes from feeling cared-for and secure.
Tiny babies, who can't feed or look after themselves, need to know someone is caring for them at all times, and are programmed to recognise and become attached to this "someone" by sight, sound, smell and so on.
The carer therefore needs to be a constant and consistent loving presence in the child's life.
We've comprehensively blown this one by putting so many tiny children into day nurseries, so that both their parents can go out to work and feed the economy rather than the baby.
As children grow older, emotional security is associated with regularity and routine, such as family meals and a familiar bedtime ritual.
Children need adults not only to love them, but to provide regularity and to set and maintain boundaries for their behaviour. So parents have to balance warmth with a degree of firmness...
Children also need to learn communication skills, another essential element in emotional and social development.
This starts from the moment they're born, and is an important part of the bond with the carer that underpins emotional development.
As parents sing and talk to their babies, they awaken the language instinct wired deep in the human brain and provide the data through which children will learn to speak their mother tongue.
But if adults don't spend time with their children, communication skills won't develop as they should - and, in a busy modern world, many parents aren't available to play their part in this process.
Many children now spend the majority of their day in institutional care...
Ironically, in a world where there are more ways to communicate than ever before, parents communicate less and less with their own children.
There's one other absolutely vital ingredient if children are to grow strong in body and mind - one that, to the great concern of developmental psychologists, is being practically eradicated from many children's lives.
They need to play. What's more, they need to play in a relaxed, unstructured way, preferably outdoors with other children and - as they grow older - away from the eagle eyes of the adults...
Human children develop physical control and co-ordination through running, jumping, climbing, skipping or kicking a football around.
They gain first-hand experience of the world they're going to live in by making mud-pies or paddling in puddles or messing about in a sandpit, riding a home-made go-kart or climbing a tree...
Sue Palmer's book Toxic Childhood: How the Modern World is Damaging Our Children and What We Can Do About It is published by Orion Books.
Source: Daily Mail