In a rare theological intervention at a Downing Street reception yesterday, David Cameron made the eye-catching suggestion that Christians were the most persecuted religious group in the world today. (He also credited Jesus with the invention of the big society, an idea most of us assumed he’d forgotten about.)

The PM is not the first prominent figure to make such a claim. Pope Benedict XVI said it during his New Year message in 2011, Angela Merkel made similar remarks during a visit to a church in November 2012, and late last year Prince Charles spoke of “intimidation, false accusation and organised persecution to the Christian communities in the Middle East at the present time.”

Tragic news reports seem to bear this out. The destruction of ancient Christian communities in their homelands in Iraq, Syria and other parts of the Middle East, described by Tom Holland as “a crime against civilisation as well as against humanity”, has been one of the most depressing consequences of the recent turmoil. Sometimes, direct religious persecution seems to be involved, as in this week’s murder of Dutch priest Frans van der Lugt in the besieged town of Homs. Meanwhile, in Pakistan yet another absurd blasphemy prosecution came to light, this time of a Christian couple sentenced to death (and a fine!) for allegedly sending text messages deemed to be offensive to Islam.

And let’s not forget North Korea, officially the worst country in the world to be a Christian, where a few weeks ago 33 Baptist missionaries are said to have been sentenced to death on the personal orders of Kim Jong-Un.

The persecution of Christians has been the subject of some recent books. The US Catholic journalist John Allen entitled his The Global War on Christians, maintaining that Christians as a whole were “indisputably ... the most persecuted religious body on the planet”. Writing in the Spectator, Allen commented that,

the world is witnessing the rise of an entire new generation of Christian martyrs. The carnage is occurring on such a vast scale that it represents not only the most dramatic Christian story of our time, but arguably the premier human rights challenge of this era as well.

In slightly less apocalyptic vein, British author Rupert Shortt in his recent book Christianophobia: A faith under attack catalogues violent targeting of Christians from Nigeria to the far east as well as less lethal but clear human rights abuses and intimidation. In an interview with Alan Johnson, Shortt said that “in a vast belt of land from Morocco to Pakistan there is scarcely a single country in which Christians can worship entirely without harassment”.

In the same interview, Shortt also lamented the “liberal blind spot” which, he suggested, made western politicians over-cautious when it came to the persecution of Christians abroad, especially in majority Muslim countries, while at the same time being “very very sensitised to the perceived sufferings and complaints of Muslims”. Post-colonial guilt, a political and intellectual history which since the Enlightenment has often pitted the forces of progress against a reactionary and over-powerful Church, and some Christians’ own tendency to turn the other cheek (including on behalf of Christians in other countries) were also, he thought, reasons why the subject of anti-Christian violence and persecution have achieved relatively little prominence in public debate in Britain.

Shortt didn’t quite say it, but I wonder too whether anti-Christian persecution is an unfashionable cause because it has been co-opted by campaigners who see equivalence between, say, the Peshawar bombing of 22 September 2013 in which 78 Pakistani Christians were murdered at their church, and the case of Islington registrar Lillian Ladele whose “persecution” involved being asked to conduct civil partnership ceremonies.

Perhaps “persecution’ isn’t the most helpful word. It is invoked to describe such disparate phenomena as inter-communal violence in Nigeria, the Democratic Republic of Congo or, most recently, the Central African Republic (where Christians are as likely to be the perpetrators as the victims of atrocities against members of different religious communities) the legal discrimination against Christians in Egypt (where, for example, church building is severely restricted) and Saudi Arabia (where Christians aren’t even allowed to worship openly) or low-level harassment and bad community relations, some of which can be found even in Europe. Tempting as it is to subsume all the unfortunate experiences undergone by Christians identified by their religion under the concept of “persecution”, it may not actually be very helpful.

Reliable figures are hard to come by and, where they exist, disputed. Last year a senior Vatican official told the United Nations that 100,000 Christians were martyred annually – a figure that would dwarf the achievements of even the most anti-Christian Roman emperor possessed of the hungriest lions. It turned out, though, that the great majority of these deaths occurred during the long-running civil war in the Democratic Republic of Congo and thus could only indirectly (if at all) be described as Christian persecution.

Rather more rigorous data has been assembled by the Pew Research Forum in a report produced earlier this year. Pew found that official “restriction on religion” (a more objective term than “persecution”) was at the highest level for six years, as was the “social harassment” of members of religious communities. And Christians, indeed, were the most affected group. Christians faced harassment in no fewer than 151 countries worldwide – and not just in the Middle East, China or North Korea.

Undoubtedly a serious finding. To some extent, however, the high figure for Christians is an artefact of the statistics. Christianity is the world’s largest religion by number of adherents, so it shouldn’t come as too much of a surprise to discover that the largest number affected by what might be described as persecution are Christians. That would be the case if members of all religions were equally affected by persecution. By the same logic, one would expect Muslims to be the second most persecuted group. And so Pew discovered: Muslims suffered harassment or restriction in 131 countries worldwide.

It’s almost certainly not the case that Christians are the most “persecuted” religious group in proportion to their numbers. Rather, they suffer along with other minority groups from, to take the most obvious example, the increasing prominence and, in some countries, power of strains of Islam that are uncomfortable with the very notion of religious pluralism. So, to an equal or even greater extent, are Muslims belonging to minority sects, such as the Shia in Saudi Arabia or the Ahmadi in Pakistan. Persecution against the Ahmadis, a sect not regarded by some orthodox as Muslim at all, has spread even to Britain, where recently a local newspaper in Luton was prevailed upon to apologise for the “hurt feelings” of Muslims after it carried an advertisement from the Ahmadi community.

If Christians are persecuted in many parts of the world, so are Muslims, Hindus, atheists, Buddhists and Jews. If Christians are persecutors in other (or sometimes the same) parts of the world: as are Muslims, Hindus, atheists, Buddhists and Jews. The fact that such a list of persecutors can include Buddhists, probably the faith least renowned for its zeal or intolerance, is a strong indication that by and large we are dealing with group rivalries, hatred of minorities, political struggles and only rarely a persecution based in the specifics of Christian theology.