The reason American children are so fat has less to do with the sort of television they watch and more to do with their parents' choices.

Is it just me or does it seem un-American for Mickey Mouse of all, er, people, to swear off junk food because Michelle Obama, the naggiest first lady since that busybody Eleanor Roosevelt, asked him to?

Sorry, but I have been in touch with my inner libertarian since New York Mayor Michael Bloomberg announced plans to ban the sale of giant sodas, thereby making New York the only city where you can buy a 40-ounce (1.2l) vat of malt liquor, but not a 40-ounce tub of Coca-Cola.

Nevertheless, as the father of three small children I welcome Disney's move, though do not forget last year's report that Disney has quietly begun marketing to newborns and, yes, preborns.

"To get that mom thinking about her family's first park experience before her baby is even born is a home run," Disney's consumer products chief told The New York Times , presumably with a straight face.

That Mickey can be a real rat.

Be that as it may, parents can use all the help we can get helping our children navigate sensibly through the aggressive culture of marketing.

My wife and I realised what we were in for shortly after our first child was born.

It turns out marketers had discovered that babies learn to recognise brand logos very early. That cute little book a kindly aunt had sent to our one-year-old to help him play creatively with his breakfast cereal in his high chair? It was actually a savvy attempt by Cheerios to imprint brand recognition on his impressionable baby brain.

He is 12 now. Cheerios is his favourite cereal. Coincidence? Hmm.

We turned into hostile helicopter parents about marketing to our children. We restrict what they can watch, and have taught them the habit of muting commercials. If there are fewer commercials promoting junk food to kids, well then, hooray.

Parental passivity

The problem is that you cannot lay all the blame at the foot of marketing. After a certain age, peer culture is more influential on children than parental instruction.

American children these days are accustomed to having sugary snacks after every outing or minor group activity.

The parent who will not serve a Capri Sun and a bag of crisps after a play-date is thought of as some sort of pervert - the same sort of weirdos, as a matter of fact, who would not let their kids watch television.

Media playback is unsupported on your device Media caption Michelle Obama hailed Disney for changing its business model to tackle obesity

Come to think of it, it is good that there will be fewer junk-food commercials on children's television. But it would be better - much better - if the kids were not watching TV at all, but were outside playing.

Which brings us to a more fundamental problem: absence of parenting.

For some reason mothers and fathers these days find it all but impossible to say "no" to their children.

It is not a secret that childhood obesity rates are sky-rocketing, and that junk food makes children fat. Nor is it a secret that parents largely control their children's access to food.

True, television commercials make it harder for parents to exercise authority over their children's consumption habits, but also more necessary. Parental passivity and abdication of responsibility for their children's diets is appalling.

'Mean Mommy'

And it is part of a bigger challenge. I have recently talked with several teacher friends, both from state schools and, in one case, a posh private academy.

The teachers all complain that the mothers and fathers of their students expect them to assume the role of parent, imparting basic instruction about manners, personal responsibility, health, and such-like.

The food writer Michael Pollan got it right when he said: 'Don't eat anything your great-grandmother wouldn't recognise as food.'

A teacher whose students are mostly poor is so discouraged by having to mother her kids that she is thinking of leaving the profession.

A teacher from a school where students pay $18,000 (£12,000) a year in tuition told me that the well-off parents figure that for that price, the school should effectively take on the role of mean parent, freeing actual parents to be their children's cool older friends.

There is nothing wrong with the government restricting advertising to children, nor is there anything wrong with a big corporation like Disney voluntarily restraining child-focused marketing.

But nothing can substitute for engaged, discerning, and authoritative parenting - exactly the sort that contemporary Americans seem unwilling to do.

Lettuce-nibbler?

If parents prefer to molly-coddle their children with junk food it surely has something to do with their unwillingness to be more responsibly austere with their own diets.

I was an obese child - yes, I had unrestricted access to junk food growing up because in our house food was love - and have struggled with my weight all my life.

Eating more sensibly, both in terms of quality and quantity, was something I had to teach myself as an adult. It takes time, effort, and a conscious commitment to be counter-cultural but it is possible to conquer a dependence on processed food and massive quantities.

It does not require one to become a pale and parsimonious lettuce-nibbler.

The food writer Michael Pollan got it right when he said: "Don't eat anything your great-grandmother wouldn't recognise as food."

He meant that the less processed our food, the better it is for us.

He also implied that our great-grannies knew how to cook and did not rely on pre-made foods, which tend to be high in fat and carbohydrates.

True, many modern families do not have the time to prepare all their meals from scratch. But there are shortcuts and they are easy to learn.

I have observed, though, that in the kitchen and at the table many people, no matter what their income, prefer to practise learned helplessness rather than take responsibility for themselves and their children.

As the food writer Jane Black has observed , studies show that Americans do not lack information and opportunity to eat more sensibly - they just prefer the taste and convenience of junk food.

So, bully for Disney and Mrs Obama, but let us be grown-ups about this: the reason American children are so fat has less to do with the sort of television they watch and more to do with the fact that American adults - the people who are supposed to be taking care of kids and forming their character and habits - would rather eat like children: what they want, as much as they want, when they want it, and cooked by someone else.

People may say they hate the nanny state, but they sure do live like they need a nanny.

Rod Dreher is a senior editor of The American Conservative. Email: rod.dreher@gmail.com