It was one o'clock in the morning. John Lutz had just left the Grand Palace Stadium cinema complex in the wealthy LA suburb of Calabasas and was standing next to his Mini, smoking a cigarette. As he did so, a massive SUV - the kind that does 10mpg - pulled up alongside him. The driver opened his window, leant out, and said: “Hey, buddy, you can't smoke here.” John, a staff writer for a popular American TV show, was unaware that an hour earlier, at midnight, the Calabasas Comprehensive Secondhand Smoke Control Ordinance - the most restrictive anti-smoking policy anywhere in the world-had gone into effect.

“You don't read the news?” chided the SUV driver, wagging his finger. “You can't smoke outdoors anymore. Put it out.” John paused for a second, unable to believe that his decision to smoke a Camel Light in an empty car park in the wee hours of the morning was of so much interest to a complete stranger. He exhaled slowly. He balled his fists. And then he told the driver - using language not suitable for publication in this newspaper, that no, actually, he wouldn't put it out.

Welcome everyone, to Nannyfornia: Birthplace of the Ban, Capital of the Clampdown, Mecca of the Moratorium. Or you could just call it the new Mild, Mild West.

The outdoor smoking ban of which John Lutz ran foul is just one example of a frenzy of puritanical edicts from California's politicians that in the past few weeks has outlawed trans fat in all restaurant food, prevented LA supermarkets from handing out plastic bags, and put a halt to fast-food joints opening in the suburb formerly known as South Central. Other recent bans -and attempted bans - have challenged such monumental threats to human wellbeing as helium balloons, camp fires, circuses, swearing, texting while stopped at traffic lights, anything made from a dead kangaroo, dogs sitting on drivers' laps, homeschooling, rodeos, unordered tapwater in diners, spanking, nude beaches, and (this is true) the use of sexually-discriminating terms such as “Mom” and “Dad” in school classrooms.

Of course, some of these things deserve to be discouraged. But criminalised? “It's becoming almost like an arms race as to who can ban more things,” says Jim Ross, the veteran California political consultant who managed the campaign to elect Gavin Newsom as Mayor of San Francisco. “San Francisco bans plastic bags, then LA bans plastics, then everyone else has to. It's ironic, because the US was founded as a reaction to the colonists telling them what to do. I mean, hey, when are we gonna start banning alcohol again?” It is true, of course, that the Golden State has always had a reputation for well-intentioned meddling - hence the reason they call it “the Left Coast”. But until recently, with Arnold Schwarzenegger serving as the Republican governor, California seemed to have avoided many of the worst examples of nanny-stateism inflicted on, say, Britain. For example: California's ban on smoking in restaurants and bars was largely avoided when establishments built outdoor decks. Schwarzenegger himself built a “cigar tent” outside his office in Sacramento, the state capital.

California remains more laidback than Britain in other ways, too. People in LA still drive after a glass or two of wine. Tax on petrol isn't designed to punish you for not wanting to get on a bus. Speed cameras remain unheard of, and CCTV is so rare that when you land in London from Los Angeles you feel as though you have been transported from the 1970s to a dysfunctional 22nd-century dictatorship.

But things began to change a couple of years ago - around the time the Democratic Party seized control of the US Congress. The Left's confidence has grown exponentially since then with the astonishing rise of Barack Obama, and even Schwarzenegger - whose popularity has vanished along with Californians' home equity - appears to be giving in to the Democratic Party's belief that only enlightened politicians can save the idiot masses from themselves.

Take California's ban on trans fats, which essentially turned puff pastry into public enemy No 1. “We are taking a strong step toward creating a healthier future for California,” declared Schwarzenegger, a man whose very appetite for the unhealthy things in life - cigars, Hummers, marijuana, badly scripted movies involving the gratuitous use of automatic weapons and explosive devices - endeared him to the US public and ultimately won him the governorship that he is now using as a tool to prevent people from eating chicken pot pies. And this week, a new law will be introduced that intends to force restaurants in LA to display the number of calories of each item on their menus.

All this raises a disturbing question, of course: is Nannyfornia providing us with a glimpse of what Obama's America might look like? After all, Obama is a classic banner. He recently proposed banning all toys from China. He banned his own staff from wearing green clothing during his recent trip to the Middle East (green is the colour of the Hamas flag). He banned the New Yorker magazine from his press plane after it depicted him as a terrorist in a political cartoon. He wants to ban “excessive” profits by raising capital gains tax. Why? Because he thinks it's fair. No matter that the state's revenues from the tax have always gone up whenever the rate has been lowered.

Jot Condie, president of the California Restaurant Association, is one of many Americans who fears all this prohibition is going too far. “The Government here in California is banning a food product simply because it's not healthy,” he complains. “What do you ban next? Bacon fat? The possibilities are limitless.”

But is it all the fault of emboldened Democrats? Without a doubt, he says. He describes the Democratic-controlled legislature in California as “an activist government that thinks it knows what's best for us”.

“It's not just trans fat,” he says. “They're banning fast-food restaurants in parts of LA because they think we're too fat and therefore they're gonna help us.” Not that he thinks trans fat is a good thing. “Trans fat raises bad cholesterol and lowers good cholesterol so, yeah, it's a double whammy,” he says. “But in two years' time, it's gonna be a thing of the past, not because of the Government but because consumers are voting with their feet. You don't need to criminalise it. The Government has created a dangerous precedent.”

John Lutz, the cigarette smoker, says the real problem with bans is that they tend to be selective - and they usually focus, conveniently, on the vices of other people. “The people who think they have the right to tell you what to do are usually the exact same people who drive around in SUVs and drink bottled water every day,” Lutz says. “I'm pretty sure both of those things are very worst things you can do to the environment. Yet they'll go crazy if they see me stubbing out a cigarette butt in my own backyard.”

The double standards are sometimes even more dramatic than SUV-driving, health-Nazis. Take Calabasas: it might have successfully outlawed tobacco use practically anywhere within its city limits, but it was happy to be home of the headquarters of Countrywide Financial, now the subject of a federal investigation into its lending practices during the mid-2000s real estate bubble. Countrywide was at one point making so much money from home loans that there was a Ferrari dealership located almost directly across the street.

Aside from the accusations of hypocrisy, however, isn't there just something inherently un-California about trying to ban everything that's allegedly bad for you? After all, this is a state that has always faced the prospect of imminent annihilation from earthquakes, fires, floods, droughts and a multitude of other natural catastrophes. Indeed, it's often hard for Britons to understand the attitude in LA that you enjoy the good times while they last, and when things go catastrophically awry - as they always tend to do, every so often - you tough it out, you learn, and you wait for the good times to come around again. Hence the fact that in London people are convinced the credit crunch is the next Great Depression, while in LA people are just as likely to be worried about missing out on the next pre-bubble investment opportunity.

So why does California feel the urge to micro-manage people's lives - to the point were helium balloons were almost made illegal because every now and again they get caught up in power lines? Shouldn't Californians know better than anyone that a life without risk is no life at all?

“I think there's actually a little bit of one-upmanship going on,” explains Jim Ross, the political consultant, adding that West Coast politicians like to think that radical bans help them to pioneer national trends. For example: because California is the largest purchaser of school textbooks, when it passed a Senate Bill requiring “nondiscrimination” against sexual orientation in classrooms (conservatives say this essentially bans the use of the words “Mom” or “Dad”), publishers began to change the wording in all US textbooks. But Ross thinks the system has a knack of stopping things getting out of hand.

“The moderating effect of a democracy will always stop bad laws from happening,” he says. “A great example of that was when the speed limit was rolled back to 55mph. It got to the point where if you were sticking to it, you were the slowest person on the road, and you'd be creating a hazard. If a law is going to work, people have to live up to it. There's a great quote from Calvin Coolidge [the 30th President of the US] that good laws are not made, they're discovered.” In other words, says Ross, a good law is never the result of a politician feeling holier-than-thou - it's a result of the overwhelming will of the people being served.

Lutz prefers to quote that other hero of American politics: Jesse Ventura, the ex-Navy SEAL turned professional wrestler turned Governor of Minnesota. Whenever a particularly meddlesome piece of legislation turned up on his desk, he would dismiss it with a line that went on to become his personal catchphrase. “You can't legislate against stupidity,” he would say.

It's a lesson that Nannyfornia - not to mention Barack Obama - might do well to learn.

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