Here’s a question for you. Are faith schools in Britain a sign of a tolerant or intolerant society? I ask because, recently, I seem to be having more and more arguments with my students and fellow teachers who believe the latter.

These debates have been prompted by growing opposition to religious schools in the UK. A campaign by the Humanist Society has attracted significant political support, including the national teaching unions and celebrities such as historian Dan Snow and soap star turned Labour politician Michael Cashman. Campaigners have also been buoyed by opinion polls showing increasing support for an end to publicly funded faith schools, which might explain the government’s U-turn on its promise to lift the 50 per cent cap on faith-based admissions to new religious free schools.

But is it true that religious schools are an expression of intolerance? Tens of thousands of parents clearly want to send their children to religious schools. And for a variety of reasons. Religious people who want to raise their children in their faith hope that sending them to a faith school will reinforce their own efforts. Others believe that the wider values of faith schools will be ones they share and want to inculcate in their children.

For others, it is more nebulous. My wife and I chose to send our son to a Catholic school because we both had such a positive and formative experiences of our church schools and hoped to emulate that for him. And we should not forget that many parents who choose a faith school are middle class atheists that suddenly start attending church on Sundays after learning that the best local schools are church schools that require a letter from the vicar to prove they are god-fearing church goers.

I object to the last reason, but, all in all, these parents seem to me to have pretty benign reasons for choosing faith schools. Not so for the opponents of religious schools. Today, a religious school that insists on a strong moral framework and set of religious values is presented by many as divisive, sectarian and intolerant. More extreme critics compare them to cults or even suggest that sending children to faith schools is tantamount to parental abuse. This prejudice is particularly noticeable when campaigners refer to Christian Fundamentalist, Hasidic Jewish and some Islamic schools. Of course, there will be those that serve as examples of crude and sectarian teaching of religion. But that is a criticism of those particular schools and their methods, rather than a justification for denying parents the choice of any faith schools.

Many myths abound. A highly intelligent friend recently confided in me that he was glad he had decided not to send his son to a Catholic school because he had come out as gay aged 12. I was absolutely amazed at his assumption that a young pupil coming out as gay would not be supported at a Catholic school - and anyone who has any experience whatsoever of Catholic schools in the UK would see that as a deeply flawed prejudice.

The irony is that my 90-year-old devout Catholic father is angry with Catholic schools for the exact opposite reason. He constantly berates his children for the fact that his 38 grandchildren seem to learn more at Catholic schools about diversity, climate change and good diet than they do about the catechism and the teachings of the church.

I support the existence of faith schools not in spite of being a liberal but because I am liberal. And as a liberal I am worried about the way this debate is going. I fear that in the hands of the anti-religious schools lobby, liberalism, tolerance and secularism have come to mean something different from their original enlightenment meaning. In other words, these concepts have been gutted of their original intent and become words used to justify intolerance towards families and communities of faith.

For me, tolerance must allow for parental choice and freedom of religious conscience. That involves the right to freedom of religion and the right of parents to raise children in the religious ethos of their choice. In this respect, the right to religious freedom is the cornerstone on which the idea of tolerance was originally founded.

It is striking that the intolerance of religious schools appears to be growing at a time when tolerance of diversity in every other aspect of life is being championed. We are encouraged to embrace the diversity of minority groups and respect many and varied lifestyle choices. But the liberal ideal of tolerance does not appear to extend to respect for religion or faith schools. I am certainly not proselytising for faith schools or suggesting that they are any better or worse than any other schools. Indeed, I have always agreed with other secularists that you don’t have to be religious to live by a strong set of ethical and moral norms. But disliking religion and religious schools is different from campaigning to get them closed down. The word “tolerate” suggests allowing something we may not like.

I am an atheist and there is much that I dislike about organised religion, but as a liberal I accept the right of access to publicly funded faith schools and defend their right to such access in a pluralist society.

Critics of faith schools also show a lack of trust in parents. Most parents want the best for their children in terms of a good quality education in a safe and secure environment. Suggesting that religious schools are synonymous with indoctrination and using words such as abuse are insulting to parents trying to do the best for their children. And it’s not necessarily true that faith schools are divisive and polarising. Many faith schools go out of their way to teach children about other religions and organise all kinds of inter-faith activities

There is an assumption by some who refer to themselves as secularists that a secularity of the state requires that religion is a strictly private affair and should have no role in the public sphere. This is to misunderstand the term. Secularism emerged as part of an enlightenment attempt to challenge the domination of religion and the authoritarian role of the church in state matters. I applaud that and am happy to live in a secular state. But to argue that secularism requires there be no place for publicly funded faith schools is to misunderstand the idea and is to veer into illiberalism.

In Britain, faith schools have been an overwhelming force for good and continue to be so. At a time when there is much talk of the need to teach British values, yet no one in education seems to know what that means in practice, perhaps it is worth asking why faith schools seem to have quite a bit of success in inculcating a transcendental value system in many of their young people? The problem we face in Britain now is not so much religious extremism, but more a crisis of socialisation - British society does not know what it stands for. Our political and social culture is in a state of flux and our value system is so uncertain that it has the feel of a moral vacuum.

Kevin Rooney is a politics teacher in London