Other people's squiffy logic is easy enough to spot. It's our own that causes the problems. Take the unhappy case of Gabriele Torsello, the photographer seized by the Taliban in Afghanistan. His kidnappers yesterday offered to swap Mr Torsello, a Muslim convert, for Abdul Rahman, an Afghan who sought asylum in Italy after being threatened with death for converting to Christianity.
You can see the neat equivalence in the minds of the Taliban. Two converts. A trip from Rome to Kabul. And vice versa. An eye for an eye and so forth. There is just one problem: both converts would rather be here than there. And who can blame them?
Moral equivalence is a slippery business elsewhere too. The Government wants 25 per cent of all places in new faith schools to be reserved for pupils of a different faith or none. "New faith schools" here is code for Muslim schools, though the Government uses the wider term to suggest even-handedness. The Education Secretary, Alan Johnson, hinted yesterday that he may apply the quota to existing schools too. Northern Ireland, proponents say, shows that faith schools bring extremism, conflict and even terrorism.
The trouble is the facts don't stack up with the assumptions. All my years of covering Northern Ireland suggested to me that, though sectarianism is endemic, it is primarily an issue of tribal identity. Religion is merely a badge. Church schools reflect rather than cause the problem. Sectarianism is learned in homes. If schools were the cause, we should have an even bigger problem in England, where a third of all state schools are run by churches, 4,600 by Anglicans and 2,000 by Catholics.
In fact the opposite is the case. At the Catholic school my six-year-old attends, the emphasis on social justice, a bias to the poor, solidarity among nations and respect for the integrity of creation leads to the opposite of social division. As does the school in the parish I used to attend, in Manchester's Moss Side, which had kids from 42 different nationalities, and where the creation of shared social values, rooted in a religious faith, spills over to build social cohesion in the wider community.
Catholic schools were set up in Britain over a century ago to provide an education for underprivileged Irish immigrants who were deemed "enemy aliens", much as Muslims are today. They have proved a huge success, with good exam results, more ethnic minorities than other schools, as many kids on free school meals and lower failure rates with disadvantaged children. Perhaps in 100 years' time our grandchildren will look at successful Muslim schools - subjected to the normal rigours of a national curriculum and school inspections - and wonder what the fuss was about.
Researchers at Lancaster University recently surveyed two groups of 15-year-olds, whites from Burnley and Asians in Blackburn, to test classic liberal values of respect and tolerance - on race, religion and gender. On almost every count the Asians - 97 per cent of whom had a religious upbringing - scored twice as well as the white kids, only 2 per cent of whom said the church played any part in their lives.
Of course there are other factors at work, for the white working class in Burnley has walked away not just from the church but from all the old solidarity-based institutions like trade unions, co-ops and working men's clubs. But, contrary to fashionable contemporary logic, it appears that in most situations religion does considerably more good than harm.
A sweet and scathing voice of protest
I went the other day to see that old folk icon Peggy Seeger - sister of Pete and widow of Ewan MacColl. At the age of 70 she is still singing, and writing, protest songs. There was one particularly striking song, "Home Sweet Home", that counterposed a hokey motherhood-and-apple pie tune with some utterly scathing lyrics about George Bush and the war in Iraq. (She has another trenchant ditty about his attitude to Kyoto).
On stage with her was the man who is, for my money, England's greatest folk musician, Martin Carthy. There is political passion in this gentle troubadour too. He made the odd pointed remark about Tony Blair, but preferred to let history be the judge, through ballads of plain people, let down by useless leaders, struggling through adversity with courage and resigned good sense.
Two nations divided by a common sense of protest. But on the same side for all that.
* In the age before the neo-cons, American right-wingers were "realists". None more so than James Baker, the 76-year-old whom George Bush has recalled to public service to devise a viable exit strategy from Iraq (where Donald Rumsfeld, who has finally lost all contact with reality, was still saying yesterday that it was impossible for the US to lose militarily).
The last Baker Plan was way back in 1985, when he was US Treasury Secretary. Then he was one of the first world leaders to tackle the Third World debt crisis - and the first to acknowledge that a solution could not be left to the market and the commercial banks, as had hitherto been the received wisdom. The formula he came up with was not perfect, but it was a massive step in the right direction.
Let's hope he can pull the same trick for peace in Iraq.