In a speech on Friday, Theresa May has pledged to bring back selection in our schools. The raft of new grammar schools the Prime Minister wishes to open will not provide parents with more choice about where to send their children. It is anti-choice.
The schools choose the children not the other way around. Grammar schools create a binary schools system. You either pass the test to get in, or you don't and go to the local non-selective school.
Theresa May wants to return to an outdated system where children are placed in segregated schools depending on their exam results. And the devil take the rest.
She tries to hide her divisive approach by cloaking it in warm words, about allowing children from under-privileged backgrounds access to the best schools. However she dresses it up, this is still selection. Still winners and many more losers. Still a minority of schools classed as 'good' and the vast majority publicly branded as 'bad'.
The Prime Minister is setting education policy back decades with this pernicious initiative. And it's not just me who says this, but her own Chief Inspector of Schools, who said that we will "fail as a nation" if we return to the selective school system, and that the idea they will help the most disadvantaged is "palpable tosh and nonsense".
And he is joined by every other education expert in the country, every reputable think tank, and every sensible academic - never mind, I believe, the vast majority of both teachers and parents. Let us leave aside for the moment, the shambolic way in which the Tories have been forced to reveal they are turning their backs on the post-war educational consensus.
The leaks, the snatched photographs, the Education Secretary being dragged to the House to utter mealy-mouthed uncertainty, and then being directly contradicted by the Prime Minister this morning. This stuff would do justice to an episode of The Thick Of It.
But the details are far worse than the presentational mess the Tories have served up. The return of selection and of the segregated education that will inevitably result, will be a disaster for millions of children.
How do we know this? Because we have been here before. For every child awarded a place at a grammar school, nine were left out and left behind. In fact, the evidence is so overwhelming that even the Tories used to agree with us. It was Labour's Anthony Crosland who first encouraged Local Education Authorities to convert their secondary schools to comprehensives.
But, it may surprise many people, no Education Secretary oversaw the closure of more grammar schools than Margaret Thatcher. Many modern Tories like Sarah Wollaston MP, understand the arguments and the evidence against them. Neil Carmichael, chair of the Education Select Committee, former Education Secretaries Nicky Morgan, and even Michael Gove, and last, but not least, the former Prime Minister David Cameron.
David Cameron, unlike his successor, understood that the idea that you could provide excellent schooling for all by opening a few extra grammar schools is, in his words, "completely delusional."
All of them opposed any extension of grammar schools, which were outlawed by Tony Blair. Not only do they manifestly fail to encourage social mobility (an argument that Theresa May's rejigged proposals now seem to accept), but they stigmatise children, create a two-tier education system, and place a cap on every child's ambition.
Selection leaves young children scarred, sometimes for life. That's why I am so opposed to grammar schools. And I am guided by a few simple beliefs. That every child has value. That every child has potential, (whether it is realised at the tender age of 11 or not). That every child deserves an excellent, properly-resourced school with well-motivated, committed teachers. That no child should be left out or left behind. Because the country needs them. It is a positive, optimistic view of children, based on my values and my experience.
We don't need to separate out our children and divide them from their peers. We need to bring them together. So that they can learn from each other in a rewarding, challenging environment and become social, responsible adults. So that all can rise to reach their full potential, instead of being left behind, wasting their talents, skills and abilities.
If Theresa May wants to press ahead with this backward step, based on nothing other than blind faith, dogma and ideology, then I give her this warning - you will regret it.
You are meddling with our children's future and our country will never forgive you for it. We are richer for the contribution that every child, rich or poor, girl or boy, black or white, from every background and every corner of the land, can make to our country. The new Prime Minister has now set out the clear dividing lines between her backward-looking Tory party and Labour. She stands for the few, we stand for the many. She wants a tiny minority to get ahead. We want all children to succeed.
At a time when schools are facing real term budget cuts for the first time in nearly two decades and there is a growing crisis in teacher recruitment and retention, bringing back academic selection is an abdication of her responsibilities to every child in our country.
Every child matters. Every child has ability. Every child has potential to reach for the skies. But instead of a glass ceiling, Theresa May is now building a concrete roof over the heads of an entire generation. And I, like many others, will fight her all the way.
Angela Rayner is the Shadow Education Secretary and Shadow Minister for Women and Equalities, and Labour MP for Ashton-under-Lyne