It’s a nightmare image: A hulk of a man, his head inflated by an outsize helmet, a flak jacket puffing up his chest, his hands clenching an M-4 rifle, violates the intimacy of Afghan villagers’ homes, their living quarters shielded by thick mud walls, bony children sleeping jumbled in a single vaulted room with their careworn parents.

The sleeping Afghans and Staff Sgt. Robert Bales, charged with murdering 17 civilians in Kandahar province, could hardly be less similar. Yet the irony of the recent tragedy is how alike are the alleged killer and the killed. I know them both. I grieve for them both. For both are called to bear the brunt of a war whose basis in falsehood and self-deception is growing daily more untenable.

Six years ago, I was working with villagers to plant roses in the same area where the March 11 massacre took place. Zingawat is the local name for the group of hamlets. Arghand, the manufacturing cooperative I founded in 2005, produces skin-care products from the stunning variety of flowers, fruits, nuts, herbs and pungent roots that miraculously flourish on that arid ground. Rosa damascena — with its sparse and fragile petals of vivid magenta — is one of only a few varieties in the world from which precious rose oil is extracted, the base of most fine perfumes. It is indigenous to Kandahar. I dreamed of replacing opium poppies with fields of roses.

In the spring of 2006, a different atrocity was visited on Zingawat. Up to 30 civilians were killed during a battle between NATO forces and the Taliban. Back then, Kandaharis were still giving the international presence the benefit of the doubt. Women from my cooperative came back from a visit to the hospital seething at the Taliban-style black turbans worn by the wounded there.

But so many mistakes have been made in the intervening years. So many apologies have been tendered, only for a fresh mistake to shatter more lives. In January 2008, for example, Canadian soldiers shot dead the sharecropper of one of my cooperative members, an old man who helped cultivate the pomegranate trees, and his 7-year-old son. They were returning from the orchard, where they had been digging irrigation channels for wheat. The Canadians mistook the spade on the man’s shoulder for a rocket launcher and fired, cutting the two of them down in the mud.

In the fall of 2010, as part of the troop surge into Kandahar, U.S. forces built a road through another cooperative member’s land, opening a swath through his grapevines. Because it broke their line of sight, they blew up the family’s raisin house, a thick-walled building used to dry perfumed local grapes. All of nearby Zingawat — Zingawat, again — suffered similar destruction that autumn: Empty buildings that the Taliban had booby-trapped were smashed, mulberry trees cut down, ancient irrigation channels filled with rubble. Kandahar’s economy has not recovered.

As for the men who wrought that destruction — men much like Bales, sentenced to spend a year in a tiny outpost, their pup tents sunk in inches of talcum-powder dust, youngsters whose watchful eyes dart to the surrounding fields just a slender coil of razor wire away — I know them, too. From 2009 to 2011, I was a special adviser to two commanders of the international troops in Afghanistan and to the Joint Chiefs of Staff. I have visited hundreds of troops in their outposts and trained hundreds more before their deployments to Kandahar.

They are the best our country has to offer. Like Bales, his past marred by alleged financial fraud, and like some Zingawat villagers who may have helped the Taliban, many of them are not untarnished. But I have found them to be remarkable men and women: generous, driven to serve a greater cause than personal comfort or advancement, and straining to acquit themselves in everything that is asked of them, from local government to preindustrial agriculture to — right — killing other human beings.

And this war is chewing them up, just as it’s chewing up the villagers in Zingawat. Never before has so much been asked of such a small segment of the American population. A startling proportion of the troops I’ve seen in Afghanistan have deployed three or more times: They make up less than 12 percent of the less than 1 percent of us in uniform. They endure multiple tours, layering scars on top of scars, becoming strangers to their children, unable to readjust to family life before shipping out again, bearing physical and psychological wounds in aching loneliness.

If only there were a clear reason for such suffering. But the worst of this tragedy is that these ordinary people — U.S. soldiers and Afghan civilians — are absorbing the cost of a failing policy that is increasingly divorced from the reality it is creating on the ground. That divorce makes dramas such as the Kandahar massacre almost inevitable.

We are told that Pakistan is a difficult ally with which we have to work. But how can a country that funds, equips, trains and directs the very militants our soldiers are fighting be considered an ally? Imagine Washington openly financing North Vietnam in 1970.

We’re told that the Afghan government is democratically elected and legitimate. But what legitimacy can derive from a 2009 presidential election in which the fraud was so egregious — the sale of voter-registration cards such as the ones I bought that March, the ballot box stuffing and the assaults by uniformed police at polling places were so ostentatious — that the actions seemed designed not just to ensure a victory for Hamid Karzai but to send a message to the people that their voices will never count? U.S. officials never grappled with this massive violation of trust.

We’re told that Afghanistan is too poor even to pay for its own army. What about the estimated $2.5 billion extorted from Afghans in bribes in 2009, not to mention the diverted customs revenue, smuggled natural resources, influence-peddling, and international contract and banking fraud? The U.S. government has explicitly decided not to address this massive corruption. How can we blame Afghans for suspecting our motives?

U.S. soldiers are expected — by military as well as civilian officials — to make up for these political and diplomatic failings. The troops’ efforts to improve Afghan forces are called the linchpin of the U.S. strategy. For another year or so, soldiers will stay camped out in places such as Zingawat, holding ground taken from the Taliban. We are told that any damage done is necessary, for U.S. soldiers are protecting the population — in other words, that if they destroyed the village, it was to save it.

What is the cost of a policy explained in such terms as these — a policy based in such delusion? It is no wonder that it drives men mad, Afghans and Americans alike.

Bales will stand trial. Afghan civilians will pay, too, dying as U.S. forces draw down and leave a government so rotten with corruption that many predict its implosion. But what accountability is there for the leaders, Afghan and American, whose poor decisions brought about such tragedies?

Sarah Chayes lived and worked in Kandahar for most of the past decade, then was a senior adviser to the U.S. military. She is the author of “The Punishment of Virtue: Inside Afghanistan After the Taliban.”

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