I was there, actually in the room, for the critical moment in David Cameron’s leadership of the Conservative Party. Which is pretty good going, because Mr Cameron didn’t manage to make it there himself.

In his defence, the whole thing took place 13 years ago. And it was at the Labour Party conference. I am sure he watched it on television. Not the same as seeing it live, of course, but we can’t all be lucky, can we?

Anyway, there I was, balcony seat, left-hand side, Blackpool Winter Gardens, when Tony Blair made one of the most significant political speeches of the postwar era. The one in which he announced that he intended to rewrite Clause Four of the Labour constitution.

And sitting next to me was George Osborne, a young researcher sent by Tory HQ to monitor proceedings. When the speech was over, we went to lunch. We agreed that politics had been altered fundamentally. If Mr Blair succeeded in turning Labour into a centrist party, the Tory party would have to change, moving towards the centre itself, or lose. And keep losing. A few years later, on bike rides to the House of Commons, Mr Osborne set about persuading his close friend David Cameron that this analysis was inescapable.

But the depressing thing is that so many people on the Right still appear to think that they can escape it. Never mind having their own Tory Clause Four moment, they haven’t yet come to terms with Labour’s Clause Four moment. I watched the grammar school row unfold with my mouth wide open. How can they not get it? What’s wrong with these people?

Listen. Before the 1997 election I was having a discussion with a Conservative friend (David Willetts as it happens) about how bad the result would be. As bad as in the Labour landslide of 1945? Or worse, as bad as when the Liberals swept to power in 1906. We were both wrong, it was a catastrophe for the Tories unequalled since 1832. It was just as bad in 2001. And pretty much the same in 2005.

So you don’t have to have a PhD in political strategy to realise that the Conservative Party now has to change. It has to compromise many of its long-held opinions in order to get some new people, people who are uncomfortable with existing Tory policy, to join in and give it support. It has to broaden its coalition. A lot. It simply can’t win, or even come close to winning, if Labour is fighting on the centre ground and the Tory party isn’t. Margaret Thatcher beat Michael Foot and Neil Kinnock not Blair or Brown. Labour has changed and the Conservatives have to respond. Simple, yes? But so many Tories still don’t seem to understand.

Amazingly, hilariously, petulantly, tragically, doltishly, persistently, bizarrely, infuriatingly, arrogantly, obtusely, fantastically, so many Conservatives appear to believe that no compromise, or at least very little, is needed. Yes, in theory, they accept the need for change. It’s just that in practice they oppose every compromise with reality and the voters that anyone suggests. This is, as Mr Cameron put it, delusional.

One of the great ironies of the Tory debate is that the people who accuse Mr Cameron of being all style and no substance also believe that the Tories can win by changing style and refusing to change on substance.

But of course, they can’t. My old friend Norman Blackwell, with whom I worked closely and happily when he was head of John Major’s policy unit, has spoken up in defence of the Tory 1997 policy of having a grammar school in every town. He thinks that policy is a good one. Of course he does. If he didn’t, he wouldn’t have put it in the manifesto, now would he? But I am sure that he noticed that the campaign in which this policy had a starring role did not have a happy ending.

So what policies in the 1997 manifesto does Norman, or any other of the grammar school critics, think should be changed? None is not a tenable answer.

Characteristically, this weekend Michael Portillo described Graham Brady, the frontbench spokesman who resigned over grammar schools, as a plodder. Charming, eh? He then suggested Mr Brady had won the argument. I think both these judgments are wrong. I wasn’t persuaded by what Mr Brady had to say but I have always held him in high regard. He is no plodder, but he has been hugely self-indulgent.

Yesterday morning a Times Populus poll showed that 36 per cent of people supported Mr Brady’s grammar school policy while 60 per cent backed that outlined by David Willetts. Even if Mr Brady was right, how often does he think the Tory party should go to the country advancing big ticket manifesto items that the vast majority of voters do not like? Grammar schools isn’t Clause Four. It’s only one issue among many where the Tories will have to change. But what does Mr Brady think – that in an election, schools policy won’t come up?

He has been praised by many for a principled resignation. I just think he wants the Conservative Party to be the best-dressed corpse in the morgue.

Moving towards the centre is painful for Tories. It starts with accepting something they are very reluctant to accept – that Tony Blair was a substantial figure who has changed the basis of political debate. And it continues with something even more painful – giving ground on policy, accepting that some arguments are lost and others will have to be returned to on another day.

Some may think that there is a brilliant, attractive, right-wing synthesis, a magical narrative that obviates the need for any concessions to the centre. Well, if there is, please don’t keep the secret to yourself. Share it with the rest of us.

Tories have a choice. They can be a tight, right little party or they can win. They can’t do both. Make up your mind. Which is it going to be?

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