The government is embarking on a monumental folly by backing London's bid to host the 2012 Olympic Games. The best we can hope is that the bid fails
Am I a bad loser? Readers of this magazine will know that I have argued against a bid for London to act as host for the Olympic Games in 2012. But Tessa Jowell, secretary of state for culture, media and sport, last month announced to the House of Commons that the government had decided to back a bid. Surely, then, that settles it.

Ms Jowell made a substantial statement to the Commons and then answered questions from 14 MPs, only two of whom expressed any doubts. Why, then, do I not concede that the government has catered for every eventuality, accept there is now total clarity on every aspect of the bid, and shut up?

My answer is that we are very far from total clarity and that everything Ms Jowell has said creates as many doubts as it claims to settle. Take, for example, the bid itself. In her opening statement she asserted that the "the cost of bidding will be about £17m". Only a few minutes later, though, she went on to say: "The cost identified is up to £30m, half of which we expect to come from the private sector."

I love that word "expect". It goes without saying that, if that expectation is not met, the taxpayer will have to make up the difference. And who is to say that the bid will not cost even more than £30m?

If the government cannot be clear about the cost of the bid and who will be landed with the bill for it, what about the almost exponentially larger sum of £2.375bn that Ms Jowell states staging the games will cost, should the bid be successful? After all, we know that the 2000 Sydney event cost twice the original estimate. We know that already, more than a year before the event, the 2004 Athens games are costing double what was anticipated. Can Ms Jowell promise that the same, or worse, will not happen to a 2012 London games? Of course not.

Of particular interest to readers of this magazine, staging the games in London will need a lot of, well, building. There will have to be a new stadium, because the British Olympic Association and mayor Ken Livingstone have turned up their noses at the new Wembley stadium, even though £120m of National Lottery money has been paid to make Wembley a dual-purpose stadium, able to stage both football and athletics, specifically for an Olympic Games. An athletes' village and an Olympic swimming pool will also be required.

Many of those applauding the government will head the queue to revile it if things go wrong. Remember the Dome …

Who knows whether any of these, if needed, will be ready in time? The British Library wasn't. The Millennium Bridge wasn't. The London Eye wasn't. The new Wembley isn't. The Jubilee Line extension was, but by the skin of its teeth. But let us be generous. Let us concede that the new stadium in east London, whatever it turns out to cost, will indeed be ready in time. Let us concede, further, that the games are a triumph in every way, and that by some miracle London's transport system manages to take the strain. After everything is over, what use will there be for the stadium?

There are no – repeat, no – other athletics events that require seats for 80,000. There is no football club that has laid claim to the stadium in the way that the Commonwealth Games stadium in Manchester has been converted to be the new home for Manchester City. Anybody got any ideas about what to do with a state-of-the-art athletics stadium costing (if we're lucky) around £300m? Or would it stand empty, a monument to our folly?

In any case, who knows what any of these substantial projects will cost, and whether that cost will bear any realistic relationship to what was originally envisaged? The British Library didn't. The Jubilee Line extension didn't. Wembley doesn't.

No, the Olympics in London would be staged on the back of a blank cheque, courtesy of public funds. It all sounds lovely now, but many of those at the moment applauding the government, especially Tory newspapers, will head the queue to revile it if anything goes wrong. Remember the Dome …