Defence of religious freedom is the war cry of No campaigners. It is a cynical attempt by the likes of Tony Abbott, John Howard, Eric Abetz and Cory Bernardi to divert the debate away from the core issue of the democratic right of same sex couples to be married in a civil ceremony.

Civil marriage is a state-controlled legal ceremony that has nothing to do with religion. The Catholic Church does not recognise as valid a marriage of a heterosexual Catholic couple in a civil ceremony. It will not be forced to.

The conservatives want to change the subject and muddy the waters because they know that, on the terrain of civil liberties and equal rights, they are on a hiding to nothing.

But it is cynical at another level because the right wing campaigners against civil rights for LGBTI people could not care less about religious beliefs, let alone religious freedom. The entrenched homophobic sentiment in society is not mainly based on people’s interpretation of the Bible or “the word of God”.

Anti-gay bigotry primarily reflects longstanding secular prejudices that homosexuality is “unnatural”, that gays are “perverts” who prey on children, that male homosexuals are “effeminate”, that homosexuality is a medical condition that can be “cured” and so on.

A clear confirmation that the continuing influence of these non-religious bigoted views motivates much of the No vote is that it is disproportionately men, for decades less religious and church going than women, who are set to vote No.

Attitudes in much of society have shifted away from these bigoted views. It would isolate the No campaigners to argue their gay-bashing positions, so they have attempted to mask their campaign with the spurious cloak of religious freedom.

There is yet a further level to the cynicism of these reactionaries. They rally to the defence of the churches only when it suits their right wing agenda.

When the pope speaks out for Christian charity to refugees, calls for peace, opposes climate change or defends the poor, do the likes of Tony Abbott rush to applaud him?

According to the Bible, “It is easier for a camel to go through the eye of a needle than for a rich man to enter the kingdom of God”. When did you last hear Abbott or Howard quoting this verse or the other passages in the Bible that condemn moneylenders and the rich?

Nor are Abbott and Howard in the front line defending the religious freedom of Muslims.

It is worth noting that opinion polls have repeatedly shown that the bulk of Catholics support a Yes vote. They don’t see marriage equality as a threat to their religious freedom.

But leaving aside the hypocrisy of the likes of Abbott and Bernardi, what should be the approach of the left to religious freedom?

“Religion is the opium of the people” is probably Karl Marx’s best-known quote. But he did not dismiss religion. Marx recognised that there is a material basis for religious beliefs – the oppressive conditions that the mass of workers endure. Only the elimination of oppressive material conditions will cause religion to fade away.

Moreover, religion is not simply a drug that helps people cope with a “heartless world”. It can be a protest against exploitation and oppression, which is reflected in the fact that many revolutionary movements have taken on a religious colouring.

It flows from this that Marxists are opposed to any attempt to ban religion or to persecute religious believers. Marxists defend the freedom of religious belief and worship for all.

Because Marxists support religious freedom for both believers and non-believers, we are for the complete separation of religion from the state. We oppose any form of state-sanctioned religion or governments favouring one religion over another.

We oppose the fact that in many countries there are still official state religions – whether it is the Orthodox Church in Greece, Catholicism in Argentina and Malta, Lutheranism in Denmark, Anglicanism in England, Islam in Egypt, Saudi Arabia and Iran, Judaism in Israel, or Buddhism in Sri Lanka, Thailand and Myanmar.

In England, the queen remains the head of the Anglican Church and the prime minister appoints Anglican bishops, who sit in the House of Lords. In Greece, the salaries of Orthodox priests are paid by the state.

In the US, church and state are supposedly separate, but in reality this is far from the case. The government pays for chaplains in the military, the churches benefit from innumerable tax concessions, Christian prayers are recited in various legislatures, and the motto that appears on every bank note is “In God We Trust”.

It is a similar story in Australia. The British invaders initially imposed Anglicanism and paid for the building of Anglican churches, while other Protestant faiths and Catholicism were discriminated against and at times outlawed.

Even after Anglicanism lost its status as the state religion, it used its position as the religion of the monarch to maintain itself as a de facto official religion until at least the 1960s. Formal state functions were presided over by Anglican bishops; the church maintained a prominent role in the military and enjoyed tax exemptions on its profitable real estate empire. It remained for decades Australia’s largest slum landlord.

One continuing legacy of the Anglican Church’s privileged status is the compulsory recital to this day of an Anglican prayer in parliament.

Over the decades, Anglicanism’s privileges were shared out among the other Protestant churches, and the once discriminated against Catholic Church was brought into the fold and received enormous state handouts.

Today, state schools and the military have government-funded chaplains. The churches’ vast property portfolios and business enterprises are exempt from tax and council rates.

Organisations such as the Salvation Army are contracted by the government to run an array of what should be state services – employment agencies, social housing, adoption agencies, refugee services, child support, retirement homes and hospitals.

These church-run enterprises are exempt from anti-discrimination laws. So the Catholic Church may sack teachers who don’t uphold the church’s teachings.

In practice, this rarely happens because the Independent Education Union defends the rights of teachers, and most Catholic parents would object to a teacher being sacked for using contraception, having premarital sex or being a single mother or gay. Added to this is that the church’s moral authority has been eroded by its appalling record on clerical sexual abuse.

For all the right’s furore about the threat to religious freedom, it is not the churches or religious believers, with the important exception of Muslims, who are legally discriminated against – it’s non-believers. What the church hierarchy fears is not that it will be discriminated against but that, in an increasingly non-religious society, it will lose some of its entrenched privileges and political influence.

If marriage equality is legalised, priests, imams and rabbis will not be obliged to marry same sex couples. Nor should they be. However, Abbott, Howard and Co want to go much further and use the cover of religious freedom to legalise homophobic discrimination by everyone from bakers to florists to wedding reception centre owners to car hire companies.

I know this might shock people, but baking a wedding cake is not a religious activity. I have personal experience on this score: my Catholic father was a baker and made innumerable wedding cakes. Never did he engage in a religious ritual over the cake or put holy water in the icing or call in a priest to assist him or bless it.

The influence of religion has for decades been in decline in Australia, and that is set to continue. The ruling class no longer relies on the churches for political support in the way it once did. This is reflected in large sections of the capitalist class either backing or acquiescing in marriage equality.

The main enemies of the left and the working class movement are the big capitalist corporations, the media empires, the Liberal Party, the police and the rest of the state apparatus – not religious believers, many of whom will be on our side in the struggle for social justice.

However, some of the most reactionary sections of the right are using the facade of religious freedom to rally their supporters to push back, not just against marriage equality, but against the broader struggle for sexual liberation and the rights of teachers and students. We should not give them an inch.