“You can’t buy an Afghan,” an American was quoted to me as saying: “You can only rent him. What we’re looking at is a rent-to-own programme.”

If so, the term looks set to stretch into the next generation — and the downpayments haven’t bought much. South of Kabul there are toeholds, not provinces. I have just returned from a toehold in Oruzgan, which abuts Helmand.

Ranking fourth in Afghanistan for poppy production, the province is about the size of the Netherlands and is President Karzai’s homeland. It is a landscape of towering rocky mountains, azure rivers and deep narrow valleys, tight with greenery. In the south a desert extends to the baking badlands of Kandahar. Nothing much goes on in Oruzgan.

I heard that rent-to-own quote in a Dutch desert base there — Camp Holland, where our Russian-built Antonov plane landed on a dirt airstrip. From here a force of more than 1,000 Dutch personnel is responsible for all of Oruzgan, although most of it is not really under anyone’s control. With a smaller number of Australian troops, they are trying to join up the non-Taleban “inkspots” (as they call them). Progress inches forward, but our planned visit to the adjacent town of Tarin Kowt was cancelled.

A Dutch supply convoy travelling by road from there to Kandahar had been ambushed and hit by explosives, leaving many wounded. For two nights they had been forced into what, in Africa centuries ago, the Dutch-speaking voortrekkers called a laager. But where the voortrekkers had ox wagons, our Dutch convoy had Australian-built Bushmasters.

So the whole camp was placed in a communications blackout, although we did hear of deaths in Kandahar and that the British push in Helmand had encountered trouble. I saw Oruzgan only from behind our camp’s high-security perimeter fences and filled my oven-hot days with visits to in-camp activities. There was a Dutch police college for illiterate Afghan recruits, an Afghan National Army base, an Australian-led trades training centre to teach Afghans construction skills and the usual joyless Powerpoint presentations, packed with strategies, visions and five-point plans.

“There’s no way,” a British colleague said to me at Camp Holland, “the Americans are going to lose this war.” Although I have seen no evidence of progress after a week’s return to a country I last visited five years ago, I guess he is right. I am more certain than ever that we cannot win in Afghanistan, but my conviction grows also that we cannot lose either.

We can lose interest and resolve, but if we want to keep pouring blood and money into the Afghan vortex, the vortex will maintain its answering thirst for both. And if the vortex wants to keep offering us a fight, we can hold our end up until the crack of doom. Advances and reverses will be many; none will be decisive, none a cause for exaltation, none for despair.

Robert McNamara, who died as, sweating in body armour, I flew back to Kabul, was US Defence Secretary during the Vietnam War. Today we forget that at most times during that conflict the data remained positive, the situation difficult but never hopeless. As a young hawk, I remember a media stream of encouraging stories. Until, that is, the inconclusive return on America’s huge investment became impossible to justify politically. McNamara, who started as a passionate advocate of the Vietnam War, said finally: “We were wrong, terribly wrong.” He was as mistaken at the end as he was at the beginning. You could always argue the toss.

Ditto in Afghanistan, where nothing is certain but the ebb and flow of effective stalemate. The only question is for how long and at what cost we underwrite it.

Two midnights before McNamara’s death I clambered from my Camp Holland bunk in the pitch black of a windowless air-conditioned steel box and walked in my underpants out into the heat of a moonlit night. But for the generator’s quiet throb, all was silent. The chop of helicopters, crump of artillery, whine of drones and roar of aircraft were gone. Over the fences I could see the cruel outlines of mountain ridges etched against a starry sky. Somewhere south the damaged convoy had dug in for the night. Our camp was temporarily cut off by land.

I felt like the only man awake. In huts all around me, I knew, nearly 2,000 young men lay dreaming, mostly in Dutch. And looking across towards our camp from somewhere in those gorges and mountains, there would be Taleban.

But what did they know of us, or we of them? How did we all — us and them — get ourselves into this?

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