They were brave fighting words which rang out last month from the National Press Club in Washington. The occasion was presented as "a strong public appeal in defence of life, of marriage, of religious freedom and objection of conscience" from "top-level representatives" of US Catholics, Orthodox, Anglicans and Evangelicals.

"We will not be intimidated into silence or acquiescence or the violation of our consciences by any power on earth, be it cultural or political, regardless of the consequences to ourselves", the top-level representatives proclaimed in the manner of Christians valiantly facing the lions in the Colosseum. They added, in the words of Christ, "We will fully and ungrudgingly render to Caesar what is Caesar's. But under no circumstances will we render to Caesar what is God's."

Powerful stuff indeed.

It came at the end of a 4700-word document called the Manhattan Declaration. (Some have hailed it as capable of shaking the US, others have pointed out that its title brings back distant memories of the Manhattan Project for building the atom bomb.)

Behind the hyperbole of signatories – ecclesiastical dignitaries, including a couple of cardinals, a string of archbishops, an archpriest and a number of political operators such as George Weigel, a well-known conservative and Charles Colson, a former assistant to President Nixon and founder of the Chuck Colson Centre for Christian Worldview of Lansdowne, Virgina – is nothing more than the latest skirmish in the US battle over abortion. The group behind the declaration were celebrating their victory in the US legislature in ensuring freedom of conscience for US doctors and a ban on the US funds going on scheme which could aid abortion. The two points were part of the price the churchmen were exacting for allowing forward a rudimentary health service for the millions of poor people in the US such as that country should have had decades ago.

No one who surveys the statistics of abortion in the US and the wider world can in conscience express anything but horror at the increasing casualness with which this action is being performed.

But must one not be equally horrified by the fact that the signatories chose to make no reference to the evident evil committed by the US government and its allies in their illegal invasion of Iraq? Chastened western troops are limping out of Iraq, leaving behind more than a million children, women and men lying dead in the ruins of a Mesopotamia which saw the birth of the planet's earliest cultures. Their comrades-in-arms in Afghanistan will be following them before long. Many of them leave burdened with the guilt of the numberless atrocities they and their fellow-soldiers committed from Fallujah to Abu Ghraib and Basra during the days of "shock and awe" that their commanders decreed. They return to countries whose governments to this day refuse to cut out the canker of torture, imprisonment without trial and illegal kidnapping which they claim they need to employ in what they have unblushingly described as their "war on terror" in defence of "western values".

Tell me, Your Eminences, why did you achieve nothing effective in "defence of life" during the illegal invasion of Iraq and its attendant massacres? Why, Mr Colson, did you do nothing "in defence of marriage ... and freedom of conscience" when Iraqis were being deprived – temporarily or for ever – of their spouses and children of their parents at the hands of the torturers of Abu Ghraib?

But let's not get things out of proportion about the state of religion in the western hemisphere. As the 20th anniversary of the butchering of the six Jesuits, their housekeeper and her daughter in the Central American University of San Salvador by US-trained troops of the Atlacatl Battalion was being commemorated last month the new Salvadorean government, headed by Mauricio Funes, a former guerrilla, announced it was awarding medals posthumously to victims. Funes declared he was lifting "the dusty carpet of hypocrisy" which covered the crime. Thus it is strange that no one in the Salvadorean or US army has yet been punished for the many assassinations they had a hand in.

Why did the signatories of the declaration not stop their country taking part in years of bloody horror in Central America, perpetrated for the most part by military dictatorships armed with western weapons?

Was it because the sort of people, disingenuously posing at the launch of the Manhattan Declaration as Christians in the Colosseum, were in fact the keepers of the lions?