Mystery of the Laughing Pm

It's a puzzle. Is Gordon Brown really in denial about the depths of our problems or does he have to pretend to be in denial because if he lets on how fearful he feels we would all panic? Whenever you see him these days he seems terrifically jovial, laughing merrily with whoever is nearby. That scares me enough. But would we be more troubled if his visage was invariably grim, the lines on his face etched as deep as furrows in a fenland marsh?

Yesterday, just before the start of prime minister's questions, he was joking with everyone and anyone. He even shared a gag with Messrs Cameron, Osborne and Clarke opposite him on the Tory front bench. He appeared to be very happy in his work.

I was reminded of a holiday a gang of us took in our last year at university. We drove a clapped-out Ford van overland to Istanbul. The van kept breaking down, but one of our party was convinced he was an expert motor mechanic.

Once, on top of a hill between Bulgaria and Turkey, it stopped with a terrible grinding noise. Derek could not have been happier. He spent ages under the bonnet, whistling as he worked. Now and again bits of the engine would fall off and some began to roll down the mountainside. But Derek knew he was right. In the end he was and we clunked and kangarooed more or less safely to the Bosphorus.

Perhaps that's what will happen. David Cameron tried to get him to admit we had moved from "boom" to "bust". According to the Institute for Fiscal Studies, our debts would take an entire generation to pay off. Brown quoted the same institute as saying that we were set to avoid a deep and prolonged recession. The institute seems to resemble one of those film critics who like everything and are consequently quoted on every billboard. "Movie of the year!", "Oscar, here it comes!" they say of some turkey that got one star from everyone else.

Cameron kept trying to make him admit he had it wrong. He declined. "We can play this game of student politics as long as he wants to play it, but what the country is interested in is whether we will take the necessary action!"

The Tory leader shot back. "Only one of us was a student politician - and he has never grown out of it!"

I don't know why everyone is so rude about student politics. It may be far more vicious than real, adult politics, but at least students can't do the rest of us much harm. Until they grow up, that is.

Both sides ended with their prepared thunderous soundbites. The effect is as if someone was trying to sing Nessun Dorma to the last bars of the 1812 Overture. Cameron said we were watching the death throes of a failed government. Brown barked that at least Ken Clarke had the right idea, which meant "agrees with me on everything". Clarke sat shaking his head.

Soon it was over and the prime minister disappeared to find someone else to have a laugh with. Home secretary? Tea lady? Anyone will do.