By Paul Goodman
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Tony Blair writes as follows in his memoirs:
"I knew that if we put up the top rate of tax it would be seen as a signal, a declaration of intent, an indicator whose impact would far outweigh its intrinsic weight. When Gordon suggested it prior to the  election and I was given the usual opinion-poll guff showing 70-80 per cent in favour of it, I put in a complete nolle prosequi. For me, it was a total red line. After time, Gordon backed off."
Unlike at least one Conservative member of the Cabinet, I have never slept with Blair's book by my bedside. But he won three elections as Labour leader, and knew what he was about.
And lo and behold, this morning's ICM poll for the Guardian finds that 67% of those surveyed want to keep the top rate at 50p.
The point I want to make isn't just that David Cameron and George Osborne should ignore "the usual opinion poll guff" about the 50p rate. It's that they should ignore all of it – when applied to tomorrow's budget measures and the next election, at any rate.
To give another example, the Independent recently carried a headline declaring “Squeeze the rich! Poll shows public want budget to redistribute wealth”.
This drew the following response from Dominic Lawson: "Well, of course they do. Since nobody thinks of themselves as rich there will always be a majority in favour of the idea of transferring money from the “them” to the “us”." He was right.
Polls are very useful in some ways. Those such as the ICM one in question are a serviceable snapshot of, say, how people would vote were there an election now. Our survey this morning gives a useful insight into the priorities of Tory party members.
But as guides to how the electorate will cast their votes in three year's time, polls are useless. 2015 is a light year away in politics.
And finally, with Cameron and Osborne reportedly playing role-reversal on the 50p (with the Chancelllor's position mirroring Blair's and the Prime Minister's Brown's) here, to close, is Blair again:
"Of course, you can make a perfectly good case for wealthy people paying more, and around the edges – National Insurance and so on – I was content that they did, but I wanted to preserve, in terms of competitive tax rates, the essential Thatcher/Howe/Lawson legacy. I wanted wealthy people to feel at home and welcomed in the UK so that they could bring more business, create jobs and spread some of that wealth around."