This week, Lord Carey, the former Archbishop of Canterbury, helped launch a campaign to persuade Christians to show their faith in public. It is called "Not Ashamed" - a title that encourages timid believers to acknowledge their religious identity in public and also recognises that more and more British Christians are no longer prepared to tolerate taxpayer-funded suppression of the visible expressions of their religion.

Christmas is the right time to make a stand, because - despite the secular, not to say tinselly, character of most festivities - it provokes some of the worst excesses of multicultural intolerance. Over the past decade, Christmas cards have been censored, Christmas decorations banned and, most offensively of all, nativity plays stripped of their Biblical content.

Why has it taken until now to mount a campaign against these measures? One answer is that, until this year, Britain had a Labour government that was deeply estranged from its Christian socialist roots. The Coalition does not claim to be a Christian administration; but David Cameron is at ease with the country's religious heritage in a way that Gordon Brown was not.

One way the Prime Minister demonstrated his approach was by supporting the visit of Pope Benedict XVI to Britain in September.

Those four days were memorable for Anglicans and other Christians as well as for Roman Catholics, because the Pope used the opportunity to proclaim Christian values from the physical heart of the British establishment.

In doing so, he was echoing the message of increasing numbers of Church of England bishops who realise that symbols of Christian faith are vital for the spiritual lives of believers - and are also appreciated by those millions of Britons who are not religious, but live according to the principles of charity and tolerance upheld by Christianity.

The Not Ashamed campaign is a long overdue challenge to politically correct orthodoxy. Its self-confidence in the face of dreary cynicism lends a new cheerfulness to this Advent season.

END