Barack Obama: Lighting up and chowing down on hot dogs - the President understands the political power of bad habits

Citizens of any nation could be for forgiven for believing that as their leaders do, so reasonably might they. North Koreans are at liberty, therefore, to murder uncles and the French to juggle multiple mistresses so ineptly as to cause one to be hospitalised. Americans, meanwhile, can smoke both cigarettes and pot and publicly gorge on hot dogs.

This is the example set by Barack Obama, which might surprise you as he seems a clean-living sort of fellow. But yesterday a small ripple of surprise was running through this land after he suggested to the editor of the New Yorker, David Remnick, that smoking joints really isn't so bad and preferable to imbibing booze. He also went on to remind us that he himself had indulged in weed and tobacco. (Though not any more, we are led to understand.)

"As has been well documented, I smoked pot as a kid, and I view it as a bad habit and a vice, not very different from the cigarettes that I smoked as a young person up through a big chunk of my adult life. I don't think it is more dangerous than alcohol," he said in a lengthy interview. As for his daughters, he said he would tell them merely that ganja-smoking might be a "bad idea".

He was asked about marijuana, of course, because since the start of this year it has been legal for Coloradans to smoke it for fun as well as for medical reasons. Pot shops are popping up faster in Boulder than 7-Elevens. Washington on the west coast is due to follow suit within months and other states are thinking about it.

While recent opinion polls have shown a slight majority of Americans in favour of legalisation, those still wary, including parents of teens researching the price of Greyhound tickets to Denver, will surely be dismayed by the president's words. Couldn't he have said pot-smoking addles the senses, causes sofa-bound stasis and has bad side-effects such as spikes in consumption of crisps, popcorn and other munchable but unhealthy packaged foods?

Not really, because Obama's record on that front is shaky enough that a group of doctors a couple of years ago released a petition begging him to stop eating fatty, artery-congesting food and admonishing the White House for repeatedly releasing photographs showing him in the act. One such had Obama carefully biting down on a juicy frankfurter with David Cameron while at an Ohio basketball game. If there was ketchup too you couldn't see it.

Obama, with the PM's help, was in fact mimicking one of his Oval Office predecessors who perhaps also underestimated the example-setting powers of his office. "Widely publicised photographs of President Franklin Delano Roosevelt eating a hotdog are credited with pushing a generally unpopular product into national prominence," the doctors said. Americans now eat seven billion hotdogs each year in the months of summer alone.

Actually, snaps of Obama reaching for waffles, frozen ices, pancakes and burgers are almost always in election campaign settings. There is no better place for politicians to find voters than in an IHop or Wendy's and no better place to project the message that they are just like everyone else. Wafting into a branch of Whole Foods to sample arugula varieties would by contrast open the candidate to charges of elitism and out-of-touchness.

Obama doesn't need to worry about being re-elected, which means he never needs to eat a double quarter-pounder with cheese ever again if he doesn't want to. And he swears he's over cigarettes, although giving them up was as hard for Obama as for any habitual smoker. In 2009, he admitted he had lit up on occasion during the previous year's election campaign but said he was "95 per cent cured".

Best we know, he hasn't touched a cigarette since he signed his health-care overhaul law in 2010. How he did this was revealed last year when he was caught on an open microphone speaking with a top UN official who also had been struggling to give up. "I chew Nicorette," he explained. But he had another secret weapon beyond nicotine gum – spousal disapproval. "I'm scared of my wife," he said.

Of course, he could still put his lungs where his mouth is and light up a spliff in the Lincoln Bedroom, though I'm guessing Michelle would have something to say about that.