'We tortured some folks,' Barack Obama admitted the other day, in a speech hailed as an unflinching mea culpa for the post 9/11 'enhanced interrogation' programme. It's not the first time Obama has reached for the F-word. In a speech in New Britain, Connecticut, earlier this year, Obama addressed the spiny question of the US's yawning inequality. 'There are folks at the top who are doing better than ever... we understand that some folks are going to earn more than others.' Happily, the president was battling to make sure 'hardworking folks' got a rise. They included the good 'folks who are cooking the meals of our troops, or washing their dishes, or cleaning their clothes. The country should pay those folks a wage you can live on.'

In fact, Obama folks away at the drop of a ten-gallon hat, as this anthology of his F-moments highlights. In Obama's case, it probably has its roots in the rhetorical idiom of a cerebral man who knows he's confronted with non-intellectuals and feels the need to reach down by feigning the common touch, something that he has less of than either George W. Bush or Bill Clinton. The initially defensive device has ossified into a tic.

'Folks' in US English manages to blur the edges of whatever context it washes over. In its juxtaposition of the homey and grim, 'We tortured some folks' vaguely recalls Philip Larkin's 'They fuck you up/Your mum and dad'. Like 'mum', 'folks' syrups whatever it touches. It does this regardless of whether the folks are good guys, like the hard-working Connecticutters, or bad hats like the suspected al-Qaida detainees waterboarded under CIA interrogation ('waterboarding', which sounds like a marine sport, used to be called 'water board torture'; three Japanese soldiers were executed after the Second World War for practising it on US prisoners of war). Asphyxiating people with sodden towels? Hey, we were just fucking with folks.

Maybe Obama's been reading Philip Roth. In The Plot Against America,the gentilisation programme to which American Jews are subjected after Charles Lindbergh is elected as a fascist fellow-traveller president is called 'Just Folks'. Urban Jews are dispatched to down-home farmsteads to chomp on hog roasts and hominy grits with bacon in the hope of 'Americanising' them.

Is there anything that 'folks' couldn't gild with faux hominess? 'Sure, the SS gassed some folks,' or 'Hey, we know Agent Orange gave some folks birth defects.' What name should be given to this rhetorical sugar-coating? 'Euphemism' seems, well, euphemistic. The best tag for it may be Jeremy Bentham's: 'terrorist language'.