Britain's leading conservative, pro-family organisation, the Coalition for Marriage, has just appointed a new campaign director who spent the past four years not in the UK during a time of considerable change, but in Nigeria, working on an infrastructure development programme provided to the federal Government there.

 'It was often hard work but very rewarding and I feel blessed to have spent so much time in a country for which I came to form the deepest love and respect,' Thomas Pascoe tells Christian Today.

While the 31-year-old was out there, however, this married former newspaper man – he was previously an assistant comment editor at the Telegraph – was keeping an increasingly concerned eye on the British media.

'In the end I came back because every time I opened a newspaper or a website from home and read about radical changes in respect of marriage and family life I hoped someone would do something about it,' he says. 'Eventually I realised that I needed to do so. Thanks to the support of my wife and family, as well as the patience of the team at the Coalition, I am now in place and thoroughly enjoying myself.'

The Coalition for Marriage, or 'C4M', is the UK's largest pro-traditional marriage organisation with hundreds of thousands of supporters. It was established in 2012 to oppose what it calls 'government attempts to redefine marriage and promote the traditional definition of marriage as being between one man and one woman, to the exclusion of all others and for life'.

In which case, it is tempting to ask, after the introduction of same-sex marriage, what there is left to fight over? In the press release announcing his appointment yesterday, Pascoe was quoted as saying that 'traditional marriage and its supporters remain under attack by an army of politicians and activists'.

Now Pascoe, who read Politics, Philosophy and Economics at Oxford, repeats the word 'attack': 'The slippery slope argument made when same-sex marriage was legalised has been totally vindicated. Far from same-sex marriage being a limited albeit radical reform, it is clear to me that it has ushered in an era in which the very concepts not only of marriage but gender too are under attack.

'Only two years after the first same-sex marriage we have the London Underground claiming that "ladies and gentlemen" is an offensive term, lawyers pushing hard to dismantle the remainder of our divorce laws and a hyper aggressive attempt to indoctrinate children with homosexual and transgender propaganda in the classroom well before their minds have developed sufficiently to critically assess it and often without the knowledge of their parents.'

The same release declared that C4M was 'preparing for our biggest campaigning year since the Same-Sex Marriage Act became law'. So what will this entail?

'This is not just an important year, it is critical,' Pascoe says. 'We will be fighting on four fronts: the propaganda being pushed to our children in the classroom, the Government's proposals to make gender a matter of personal choice, the BBC's determination to use its position to push an entirely one-sided view of gender, and protecting our supporters and their freedom of speech and from harassment.'

C4M's publicity also said it is sending out a new 'brochure' to coincide with Pascoe's appointment. Pascoe explains: 'One thing I was keen to do on joining was to throw some light on the activities of the Coalition. The work which it does behind the scenes runs very deep, but only a small portion of that reaches our supporters. The brochure is one way of answering the perennial question: "What can I do to help?" I will also be starting a regular blog which will hopefully provide a more regular insight into our work for those who are interested.'

This frenetic work is all very well, but is there not a straw man problem here? After all, arguably same-sex marriage merely extends marriage; it doesn't represent an attack on the ability for traditional, heterosexual couples to marry as they always have.

'I disagree,' says Pascoe. 'Traditional marriage – which is between a man and a woman, to the exclusion of all others, and for life – has always enjoyed a position quite unlike any other social institution. This is right and proper as it reflects the centrality of traditional marriage to raising children as well as family, local and national life.

'The greater the expansion of the definition of marriage, the more that the special status of marriage is diluted. If marriage no longer has anything to do with producing and raising children – a biological impossibility for a same-sex couple without a third party from outside the marriage, then it is something else, something weaker and less important. Marriage should be the gold standard for society, but our current public morality which places the individual's wish fulfilment above all else means that it is in danger of becoming simply a contract, a change which would harm the vulnerable the most, particularly children.'

Pascoe talks like a traditionalist Christian. Yet one of the curiosities about C4M, as he points out, is that it is 'not affiliated to any particular religion or church'. It seems perhaps a little bizarre to be so opposed to same-sex marriage from a non-Christian point of view.

Yet Pascoe says: 'Christians are not the only people concerned about the status of traditional marriage and our supporter base is very broad across faith groups as well as secular society.

'From a personal perspective, I would say that if we have learnt anything about the sexual revolution it's that it is remorseless. It does not stop. There is no concession which will lead to anything other than a demand for a further concession. Religious people taking the view that it is best to give up on the legal definition of marriage will not find that they are left alone. Rather, having banked that concession, the campaigners will soon turn their focus to the churches and other places of worship.'

Concluding on a characteristically pessimistic note, Pascoe cites colourful examples of what does, admittedly, appear to be a growing tyranny of social liberalism at Westminster. 'Earlier this year Justine Greening, the Education Secretary and Equalities Minister, ordered the Church of England to "reflect" on its attitude towards same-sex marriage. The Speaker of the House of Commons, John Bercow has said that homosexual couples should "******* well" be able to get married in churches.

'In other words religious people who support traditional marriage but who ignore what the state says and does in the expectation that they will be left alone, do so at their peril.'