Matthew Norman: Once you're a joke, you're doomed

Attempting to predict the next twist in this uniquely serpentine US election is a game for imbeciles, as some of us have learned to our shame, but one thing seems safe to predict. Assuming she managed to stand upright without drooling, ceding control of bodily functions or flashing a Janet Jacksonesque nipple at the cameras, Sarah Palin did better in last night's vice presidential debate in St Louis than Admiral Stockdale.

Until Governor Palin's emergence, Ross Perot's 1991 running mate stood as the leading paradigm of the buffoonish political ingénue. The sadness here is that, far from being a buffoon, James Stockdale was not only a lustrously decorated war hero, but a man of intellectual brilliance who wrote books on and taught philosophy at Stanford.

And then Perot put him on his independent ticket when no one knew a thing about him. No one. "Who am I?" was the Admiral's introductory gambit in his debate with Dan Quayle and Al Gore, "and why am I here?" At first the audience greeted this with approval, but when it seemed from his ensuing silence (in fact due to his hearing aid malfunctioning) that the questions were not rhetorical, the approbation mutated first into numbed shock and then guilty mirth.

All these years later, I remember the horror as if it were yesterday. When this ringer for Victor Meldrew's older brother – who set fire to his hat by tapping his pipe out into it – compressed a scheduled two-minute answer on health care into 12 seconds of utter bemusement, my wife literally bit the pillow. It was the most excruciating thing I've ever seen on telly, and that includes David Bowie reciting the Lord's Prayer at a charity gig. Perot still won an impressive 18 per cent of the popular vote, but he'd been polling close to 25 per cent before that debate rendered his campaign immutably farcical.

The lesson of James Stockdale is that the most lethal warhead in the anti-politician armoury isn't hatred, fear or scandal, all of which politicians frequently survive all these and sometimes turn them to their advantage. What they cannot counter is a snapshot that indelibly brands them as a joke just as they are trying to establish themselves as gravitas-laden emblems of leadership.

We have seen it here. Neil Kinnock's inaugural act on becoming Labour leader was falling over on Brighton beach, while Ming Campbell's first public utterance as acting Lib Dem leader, after the knifing of Charlie Kennedy, was a remark at Prime Minister's Questions (about schools not having permanent heads) that unwittingly directed a halogen lamp at the chaos gripping his own party, and enticed a parliamentary reaction of exaggerated mirth. He never recovered his poise.

Only last week, meanwhile, we saw the first signs of David Miliband's demise when, during his week long, one-man demonstration of world-class gurning in Manchester, the young master underlined his innate statesmanship by posing with his pet banana. If he should never have been taken seriously before, he may never be again.

In her defence, Sarah Palin has needed a little assistance in making such a swift transition from saviour of the McCain campaign to what looks like final nail in a coffin hardly in grave need right now of additional ferrous material. She's done the groundwork herself, of course, with a series of sensationally inept media forays, but the real credit belongs to the comedian, actress and writer Tina Fey. If you haven't seen Fey's two Saturday Night Live skits, where have you been and what is wrong with you? Google them at once, and set aside a couple of hours to watch them over and over again.

The fact that Fey is an uncanny Palin doppelganger (Todd, Track, Trig, Truck, Trick and the rest would struggle to pick the real one out of an ID parade) is a bonus. But the singular destructive genius of these sketches – the first a joint address with Hillary Clinton (Amy Poehler); the second a parody of Palin's calamitously vapid interviews with NBC's Katie Couric (Poehler again) – is not that Fey looks and sounds identical to the Governor of Alaska, and captures her cutesy physical gestures to perfection. It's that she often uses almost the identical words.

This is a hugely effective satirical ploy, because many a good jest is spoken in true words. Craig Brown's Private Eye parodies are never so hilariously damaging as when he gives his victim's pronouncements only the tiniest of tweaks, and so it is here. There are several majestic moments, such as her responding to Hillary's discourse on diplomacy being the cornerstone of all foreign policy with a winsome: "And I can see Russia from my house!" But the coup de grace is her answer to a bailout question that is almost verbatim what the real Palin told the real Couric... a rippling stream of semi-consciousness in which she trotted out everything she could recall from her frantic briefing sessions, in no particular order and with no attempt to make a point.

Be they Bible-bashing creationist or moose-chomping hockey mom, however red their neck and blue their Republican loyalties, no one in possession of their senses could watch these sketches and not conclude that John McCain was off his chump to use Palin as the ball for his Hail Mary pass. Tina Fey has taken the nebulous concern that there was something not quite right about an unseasoned novice being an actuarial 3-1 shot to become President on McCain's death, and solidified it into concrete fact.

However the real Palin performed in St Louis – and such are expectations that she'll have trumped them by remembering which party she represents – is barely relevant. She can no more reverse her image as a smugly uncurious, spectacularly ill-informed patsy than David Steel could reverse his as David Owen's pocket hankie after being pounded by Spitting Image.

The crucial verdict on her performance will come not today from the ponderous pundits of CNN and Fox, the sonorous columnists of the Wall Street Journal and New York Times, or the partisans of the blogosphere, but tomorrow from Tina Fey on Saturday Night Live. Sarah Palin has become the hostage of a comic titan, and that is the very last place on earth any democratic politician would care to be.