Here are three arguments for voting Tory in the forthcoming election. First, a hung parliament might spook the markets, causing a run on the pound and a refusal to buy UK government bonds. We would all be ruined and should therefore, whatever our usual allegiances, support the only party likely to achieve a clear majority. Second, a narrow Tory victory would leave David Cameron dependent on the votes of MPs who oppose action on global warming. Third, just as many natural Tories supported Tony Blair in 1997 because he cleansed Labour of any traces of socialism, so we lefties should back Cameron, because he excludes Thatcherite purists from mainstream politics.

But I can't do it, and not only because, whereas Blair believed in what he was doing, it is far from clear that Cameron does. British elections aren't merely about who you want in Downing Street, but about what kind of people you want on the government benches of the Commons and what kind of company they keep. If I ever think of voting Tory, I recall a party conference in the early 1990s where I witnessed, from a few seats away, the orgasmic excitement of overfed, red-faced delegates as speakers ranted about criminals, single mums and benefit scroungers; the minister who, at a late-night conference reception, smacked his lecherous lips while delivering his assessment of nearby women's bodies; the "jokes" about black people some Tories make in private dinner speeches where they think no one will object (or leak to the press).

I recall also the Iraq war. With Labour, there was at least, thanks to a backbench rebellion and Robin Cook's resignation, a significant chance of stopping British involvement. Under a Tory government, there would have been none.

This story appears in this week's edition of the New Statesman.

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