Do you wonder at the attitude of people who put “no turning” signs by the roadside at their gateways? Dogs in mangers, or what? A sad variant is emerging in the Peak District this summer as small herds of exhausted, exhilarated or lost Duke of Edinburgh’s Award participants straggle across the hills in rain and shine. They may congregate on the road verge, awaiting pick-ups, resting, map-reading or conferring. But at some landowners’ gates are appearing scrawled “NO D of E” boards. How mean. What an introduction for urban kids to rural England.

Darkness visible

I’m now en route to Afghanistan, and flying over Iran. Our newspapers are full of quotes from Iranian leaders about us British being the “little Satan” to America’s Great Satan; about the wickedness of the English, and about nations on the side of evil.

We tend to treat references to the diabolical as just the ludicrous hyperbole that politicians are prone to — and Iranians more than most: overheated wordplay, a florid way of saying “we don’t like you”. It wouldn’t occur to us that to any modern Iranian mind this Satan stuff could go deeper than metaphor.

But Persia is the ancient home of both Zoroastrianism and Manichaeism: religions rooted in the belief that the world is the battleground of two forces, good and evil, in mortal combat. This dualism in which there are (almost) two lords of the universe, light and darkness, was not invented by Persian seers; rather they tapped into and theorised a hunch about life’s meaning that has exerted a persistent appeal on the human mind down the ages. George W. Bush’s world view, Stalinist propaganda, the medieval Cathars and our red-top populist newspapers today are all pulled that way.

Not that you would know it from the loose language of Wesleyan hymns or the American evangelical Right, but dualism is actually a heresy in the Christian religion. Christians are supposed to believe that though evil exists there’s no challenge to God. The battle’s won. But all three Semitic monotheisms, Christianity, Judaism and Islam, are confused about the status of evil, although from what I understand of Islam thoroughgoing dualism would be a heresy there too. The heresy has clearly leaked into the Iranian Shia mindset, and when Iranian propagandists claim to see Satan among their enemies, maybe they are playing to something exceptionally strong in the Persian cultural imagination. The pedigree of ideas matters.

Far beneath my plane stretch harsh deserts and mountains, pin-pricked by habitation, I thrill and shudder to think of the mighty clashes of ideas, the bitter vigour of the metaphysics, the rich, strange doctrines that have seethed from those tiny shacks and tents and been argued along those lonely tracks whose cruel geometry is scratched across the waste. It all looks dusty, dry and brown down there. But crack the leather and beneath flows blood.

Unquestionably hard

Before leaving I had zoomed off to Cambridge to prove that Jonathan and Sir David Dimbleby’s jobs are much, much, harder than they look. I’m president of Clare College’s undergraduate politics society, and was asked to chair an Any Questions/Question Time-style session in front of a scarily large audience of parents come for the graduation ceremony, unimpressed students and clever dons. We had a great panel because lots of politicians turn out to be Clare graduates; and apart from the columnist Allison Pearson I was joined by the Lib Dem MP for Cambridge, David Howarth, the Tories’ Peter Lilley, the Justice Minister Michael Wills and Dr Richard Taylor, the independent.

But the sixth panellist, Stuart Shepherd, an undergraduate from our politics society, gave the star answer. Panellists were asked how much confidence they had in politicians’ ability to rise to the challenge of climate change. “Not much,” said Mr Shepherd, and on hearing the roar of audience approval, had the wit to terminate his answer there.

But, crikey, it was difficult being chairman. Have you ever watched Sir David or Mr Jonathan, and thought “I could do that?” Well, try it. Try controlling, without bludgeoning, a posse of minds, tongues and egos, remembering names and expertises, keeping an eye on the clock, trying to listen and engage while simultaneously orchestrating. Those Dimblebys make it look so easy. It isn’t. Afterwards, in the taxi to the station, I was nearly sick.

Five years on

Swooping down into Kabul. So many more watchtowers than when last I was here five years ago. So many more concrete barriers. So much barbed wire. A week, now, in Afghanistan. I wonder what lies ahead.

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