Same Old Story. Journalists shouldn't use the phrase, but what else can I say when I prowl through press reports? Take the following. "It is slowly dawning... that the Americans are really going home, that there will be a ceasefire in this country soon, and then a march to the US... planes." Iraq? Nope. Afghanistan? You'd be so lucky.

This is Vietnam in 1972 reported by The Washington Post. "The Vietnamisation of the ground war took place some time ago," Don Oberdorfer wrote. "Now this country is undergoing something more fundamental – the Vietnamisation of its hopes and fears about the future."

Which is what is supposed to be happening in Afghanistan today. That old report contained a lot of statistics; the South Vietnamese army had 1.1 million men under arms (the Afghans now have a notional 180,000), as well as 2,000 planes and helicopters and 1,400 tanks. And in Vietnam, at the end, everyone was complaining about corruption by the central government. For Saigon then, read Kabul today.

Let's stay in the archives for a moment. "American bomber crews in Cambodia were accused by President Lon Nol's military command yesterday of a further two cases of bombing 'friendly' villages in error... If the latest allegations of bombing mistakes are proved correct... it would bring the number of loyal Cambodian soldiers and civilians including women and children, known to have been killed by such military 'slips' to more than 150 and the number of injured to more than 300." This is from The Daily Telegraph on 10 August, 1973. For Lon Nol, read President Zardari in Pakistan. For bombing mistakes, read drone attacks, although I notice that "allegations" and "slips" are as dutifully inserted into modern-day reports as they were by The Telegraph back then. And we know what happened later. The Khmer Rouge turned on their own people – just as the super-Taliban of Pakistan have turned on their own people.

We really do not have an institutional memory. It happens all the time in the Middle East today. We are told Iran will have a nuclear bomb next year – but we forget that we've been told that almost every year for the past 15. Even the 1990s fear of "Islamicism" – cultivated by Fox News – is now being regurgitated after the Arab Awakening. Is this because we don't care about history? Or because we don't read books any more? Or because we don't know how to write – and, more to the point, broadcast – about history?

I mention this because a reader has sent me the latest, lamentable BBC television project on the Crusades, a three-part clodhopper fronted by Thomas Asbridge, a perfectly respectable London University academic. I expected a mass of clichés, lots of "plonking" commentary and utterly banal images of modern-day Arabs set beside verbal reminders of huge Muslim armies waiting to take on the Christian invaders. Indeed, episode one was so replete with clichés and Arabs – driving four-by-fours or using mobile phones – while we were told about medieval Muslims, that the series became compulsive viewing. It was so awful that you had to watch the rest.

The ferocious anti-Muslim Pope Urban II was illustrated by pictures of his statue in Clermont Ferrand; so this was what the bastard looked like, we thought, as we saw the staring eyes, the beckoning hand. Except that the statue was the work of Henri Gourgouillon, who died six years after my father was born. Some likeness. Then we had poor Tom Asbridge telling us that the Christians had discovered "otherness" and that matters became "acculturated", that the Pope had found a "target audience". The story of the Crusades was one of "religious fanaticism and unspeakable violence" in which "the wily Bohemond showed his hand".

Sure enough, the appearance of the dodgy Holy Lance had "an electrifying effect on the Crusaders' mind". Later, Crusader morale experienced an "electrifying boost". When the Crusaders first saw Jerusalem, it "must have been incredibly moving" and "defeat here was simply unthinkable", after which the Christians unleashed "a rampaging torrent of barbarism and indiscriminate slaughter" which was "Holy War in all its horror". A rampaging torrent?

Sure, young Tom got to finger some Crusader documents – he felt he was able to "touch the past", and perused a psalter which "speaks to us from the medieval world". Ho hum. I could forget that the pictures of Saladin in the Jerusalem scene were actually of the old boy's statue in Damascus. I might even have been able to forgive an entire battle illustrated by a whinnying horse and Tom's clogs running through an unidentified cornfield. I might just about stomach poor, sweating Tom at the Horns of Hattin glugging from a plastic water bottle to show just how thirsty those doomed Crusaders were when they fought there in the Palestinian desert in 1187.