The more I learnt of Pol Pot's journey to France, and of the other journeys that had preceded it, the more curious I became about his origins. One day, late in January, I decided to go looking for his ancestral village in the province of Kompong Thom.

Kompong Thom has great military importance, for it straddles the vital middle section of Cambodia: the town itself lies at the strategic heart of the country. The town of Kompong Thom is very small: a string of houses that grows suddenly into a bullet-riddled marketplace, a school, a hospital, a few roads that extend all of a hundred yards, a bridge across the Sen river, a tall, freshly-painted Wat, a few outcrops of blue-signposted Untac-land and then, the countryside again, flat and dusty, clumps of palms leaning raggedly over the earth, fading into the horizon in a dull grey-green patina, like mould upon a copper tray.

Two of the country's most important roadways intersect to the north of the little town. One of them leads directly to Thailand, and has long been one of the most hotly contested highways in Cambodia, for the Khmer Rouge controls large chunks of territory on either side of it. The State troops who are posted along the road are under constant pressure, and there are daily exchanges of shells and gunfire.

The point where the two roads meet is guarded by an old army encampment, now controlled by the State. A tract of heavily mined ground runs along its outer perimeter: the minefield is reputed to have been laid by the State itself - partly to keep the Khmer Rouge out, but also to keep its own none-too-willing soldiers in.

Here, in this strategic hub, this centre of centres, looking for Pol Pot's ancestral home, inevitably, I came across someone from mine. He was a Bangladeshi sergeant, a large, friendly man with a bushy moustache: we had an ancestral district in common, in Bangladesh, and the unexpectedness of this discovery - at the edge of a Cambodian minefield - linked us immediately in a ridiculously intimate kind of bonhomie.

The sergeant and his colleagues were teaching a group of Cambodian soldiers professional de-mining techniques. They were themselves trained sappers and engineers, but as it happened none of them had ever seen or worked in a minefield that had been laid with intent to kill, so to speak. For their Cambodian charges on the other hand, mines were a commonplace hazard of everyday life, like snakes or spiders.

This irony was not lost on the Bangladeshi sergeant. "They think nothing of laying mines", he said, in trenchant Bengali. "They scatter them about like popped rice. Often they mine their own doorstep before going to bed, to keep thieves out. They mine their cars, their television sets, even their vegetable patches. They don't care who gets killed; life really has no value here."

He shook his head in perplexity, looking at his young Cambodian charges: they were working in teams of two on the minefield - an expanse of scrub and grass that had been divided into narrow strips with tape. The teams were inching along their strips, one man scanning the ground ahead with a mine-detector, the other lying flat, armed with a probe and trowel, ready to dig for mines. By this slow, painstaking method, the team had cleared a couple of acres in a month's time. This was considered good progress, and the sergeant had reason to be pleased. Generally speaking, Bangladeshi military units have an enviable reputation in Cambodia and are said to do thoughtful developmental work wherever they are posted, in addition to their duties.

In the course of their work, the sergeant and his colleagues had become friends with several Cambodian members of their team. But the better they got to know them, the better they liked them, the more feckless they seemed, the more hopeless the country's situation. This despite the fact that Cambodians in general have a standard of living that would be considered enviable by most people in Bangladesh or India; despite the fact that Kompong Thom - for all that it has been on the battlefront for decades - is neater and better-ordered than any provincial town in the subcontinent. Despite the fact that the sergeant was himself from a country that had suffered the ravages of a bloody civil war in the early 'seventies.

"They're working hard here because they're getting paid in dollars", the sergeant said. "For them it's all dollars, dollars, dollars. Sometimes, at the end of the day, we have to hand out a couple of dollars from our own pockets to get them to finish the day's work."

He laughed: "It's their own country, and we have to pay them to make it safe. What I wonder is: what will they do when we're gone?"

I told him what a long-time foreign resident of Phnom Penh had said to me: that Cambodia was actually only fifteen years old; that it had managed remarkably well considering it had been built up almost from scratch after the fall of the Pol Pot regime in 1979, and that too in a situation of near-complete international isolation. Europe and Japan had received massive amounts of aid after the second world war, but Cambodia which had been subjected to one of the heaviest bombings in the history of war had got virtually nothing. Yet Cambodians had made do with what they had.

But the sergeant was looking for large-scale proofs of progress - roads, a functioning postal system, Projects, Schemes, Plans - and their lack rendered meaningless those tiny, cumulative efforts by which individuals and families reclaim their lives - a shutter repaired, a class taught, a palm-tree tended - which are no longer noticeable once they are done since they sink into the order of normalcy, where they belong, and cease to be acts of affirmation and hope. He was the smallest of cogs in the vast machinery of the UN but no less than the international bureaucrats and experts in Phnom Penh, his vision of the country was organised around his part in saving it from itself.

"What Cambodians are good at is destruction", he said. "They know nothing about building - about putting things up and carrying on."

He waved good-naturedly at the Cambodians and they waved back, bobbing their heads, smiling and bowing. Both sides were working hard at their jobs, the expert and the amateur, the feckless and the responsible: doughty rescuer and hapless rescued were both taking their jobs equally seriously.

Later I got a ride with an Austrian colonel, in an Untac car, a white, airconditioned Land Cruiser. He was a small, dapper, extremely loquacious man: he'd spent most of his working life on UN missions; he rated the Cambodia operation well above Lebanon, a little below Cyprus. But he was still planning to get out of Kompong Thom - too much tension, too many shells overhead.

We stopped to pick up a Russian colonel, a huge man, pear-shaped, like a belly dancer gone to seed. His khaki shorts looked like bikini briefs on his gigantic legs.

The Russian reached for the radio, which was tuned to the Untac radio station, and turned it off: "Yap, yap, yap, yap", he said, glaring at the Austrian.

The Austrian shrank back, but plunged into battle a couple of minutes later, moustache bristling. "I like that station", he cried. His voice was high, terrier-like. "I like it, I want to listen to it."

The Russian jammed a tree-stump of a knee across the radio and looked casually out of the window. The Austrian snatched his hand back, but his defeat was only temporary. He turned to look out of the window and sighed. "Such a beautiful country", he said, "such wonderful people - always smiling. But why are they always at war? Why can't they get on with building their country?"

He grinned at the Russian: "I suppose we'll be going to Russia next - eh, my friend?"

The Russian sprang bolt upright, sputtering. The veins on his temples bulged. "No", he barked, "no, not Russia, never, maybe Ukraine...But not Russia, never."

Then a truck appeared on the road ahead of us, gradually taking shape within a cloud of dust. It was packed with people, many of whom seemed to be wearing olive-green fatigues. A man was leaning over the driver's cabin, looking directly at us: he had an unusual looking cap on his head. It was green and looked Chinese, like something a Khmer Rouge guerilla might wear. The Russian and the Austrian were suddenly on the edge of their seats, straining forward.

The truck went past in a flurry of dust, the people in it waved, and we got a good look at the cap. There was lettering on it; it said: "Windy City Motel."