The row over grammar schools has been widely portrayed as David Cameron’s Clause Four moment. Nonsense. The current Conservative argument has practically nothing in common with Tony Blair’s successful campaign in 1994-95 to rewrite Labour’s aims, and remove the commitment to nationalisation.

The search for historical repetitions is usually a delusion, and often ridiculous, like the vacuous journalistic fashion for the new this or that: brown is the new black or Monday is the new Tuesday, or similar imbecilities. There can sometimes be interesting parallels but they are seldom exact and the position Mr Cameron is now in is very different from Mr Blair’s in 1994.

The Clause Four battle was almost entirely symbolic, which was why the Blairites won. Only a few on the hard Left any longer took seriously the 1918 language about public ownership in the party’s constitution. After Hugh Gaitskell’s failure in 1960 to change the party’s aims, most Labour leaders believed it was not worth having the fight. They were content to continue with an empty formula.

For Mr Blair, it did not matter that Clause Four was a paper castle. Knocking it down demonstrated that Labour was really new. It was Mr Blair’s first, and most successful, exercise in triangulation, counterposing new with old Labour, as well as the Tories.

That was an important propaganda victory and built up Mr Blair’s authority. It enabled Gordon Brown and him to proceed with more important policy changes such as the embrace of globalisation and the Thatcherite industrial relations and economic reforms, as well as offering reassurance on tax and public spending. But none of the rebranding would have worked without the changes of substance. After all, rewriting Clause Four in itself did not change any policies.

The current row is different. Unlike Clause Four, it has not been a premeditated confrontation. Mr Cameron and David Willetts were not seeking a battle, and both have disowned parallels with Clause Four. It is more cockup than conspiracy.

Not only was the Clause Four debate largely symbolic while the argument about grammar schools is about substance; the dividing lines are also different. In 1994-95, the opponents of Mr Blair’s move were a minority, on Labour’s far Left. Now the critics are not just isolated on the Tory Right, but come from across Mr Cameron’s party.

Yet both issues say a lot about the direction of their parties. Seeking to create new grammar schools, as opposed to preserving old ones, is an argument from the past. The way to help children from poorer and disadvantaged backgrounds is not to revive the 11 plus, which, I am sure, would quickly prove unpopular with voters, but, as Mr Willetts argued, to expand the Government’s city academy programme in inner cities and to make it much easier to open new schools.

Mr Willetts wants setting and streaming, as well as robust discipline, within schools rather than admission by selection. His goals are the same as his critics’. However, he understands how the world has changed.

Yet the way to win this debate is not, as Mr Cameron accepts, by a Clause Four-type battle seeking to confront, isolate, and defeat, traditionalists, as Mr Blair did in 1994-95, but by persuasion. Mr Blair could safely ignore his opponents. Mr Cameron cannot. He needs to win over his critics.

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