By NICHOLAS D. KRISTOF — New York Times.

Imagine you’re a villager living in southern Afghanistan.

You’re barely educated, proud of your region’s history of stopping invaders and suspicious of outsiders. Like most of your fellow Pashtuns, you generally dislike the Taliban because many are overzealous, truculent nutcases.

Yet you are even more suspicious of the infidel American troops. You know of some villages where the Americans have helped build roads and been respectful of local elders and customs. On the other hand, you know of other villages where the infidel troops have invaded homes, shamed families by ogling women, or bombed wedding parties.

You’re angry that your people, the Pashtuns, traditionally the dominant tribe of Afghanistan, seem to have been pushed aside in recent years, with American help. Moreover, the Afghan government has never been more corrupt. The Taliban may be incompetent, but at least they are pious Muslim Pashtuns and reasonably honest.

You were always uncomfortable with foreign troops in your land, but it wasn’t so bad the first few years when there were only about 10,000 American soldiers in the entire country. Now, after President Obama’s speech on Tuesday, there soon will be 100,000. That’s three times as many as when the president took office, and 10 times as many as in 2003.

Hmmm. You still distrust the Taliban, but maybe they’re right to warn about infidels occupying your land. Perhaps you’ll give a goat to support your clansman who joined the local Taliban.

That’s why so many people working in Afghanistan at the grass roots are watching the Obama escalation with a sinking feeling. President Lyndon Johnson doubled down on the Vietnam bet soon after he inherited the presidency, and Mikhail Gorbachev escalated the Soviet deployment that he inherited in Afghanistan soon after he took over the leadership of his country. They both inherited a mess — and made it worse and costlier.

As with the Americans in Vietnam, and Soviets in Afghanistan, we understate the risk of a nationalist backlash; somehow Mr. Obama has emerged as more enthusiastic about additional troops than even the corrupt Afghan government we are buttressing.

Gen. Stanley McChrystal warned in his report on the situation in Afghanistan that “new resources are not the crux” of the problem. Rather, he said, the key is a new approach that emphasizes winning hearts and minds: “Our strategy cannot be focused on seizing terrain or destroying insurgent troops; our objective must be the population.”

So why wasn’t the Afghan population more directly consulted?

“To me, what was most concerning is that there was never any consultation with the Afghan shura, the tribal elders,” said Greg Mortenson, whose extraordinary work building schools in Pakistan and Afghanistan was chronicled in “Three Cups of Tea” and his new book, “From Stones to Schools.” “It was all decided on the basis of congressmen and generals speaking up, with nobody consulting Afghan elders. One of the elders’ messages is we don’t need firepower, we need brainpower. They want schools, health facilities, but not necessarily more physical troops.”

For the cost of deploying one soldier for one year, it is possible to build about 20 schools.

Another program that is enjoying great success in undermining the Taliban is the National Solidarity Program, or N.S.P., which helps villages build projects that they choose — typically schools, clinics, irrigation projects, bridges. This is widely regarded as one of the most successful and least corrupt initiatives in Afghanistan.

“It’s a terrific program,” said George Rupp, the president of the International Rescue Committee. “But it’s underfunded. And it takes very little: for the cost of one U.S. soldier for a year, you could have the N.S.P. in 20 more villages.”

These kinds of projects — including girls’ schools — are often possible even in Taliban areas. One aid group says that the Taliban allowed it to build a girls’ school as long as the teachers were women and as long as the textbooks did not include photos of President Hamid Karzai. And the Taliban usually don’t mess with projects that have strong local support. (That’s why they haven’t burned any of Mr. Mortenson’s schools.)

America’s military spending in Afghanistan alone next year will now exceed the entire official military budget of every other country in the world.

Over time, education has been the single greatest force to stabilize societies. It’s no magic bullet, but it reduces birth rates, raises living standards and subdues civil conflict and terrorism. That’s why as a candidate Mr. Obama proposed a $2 billion global education fund — a promise he seems to have forgot.

My hunch is that if Mr. Obama wants success in Afghanistan, he would be far better off with 30,000 more schools than 30,000 more troops. Instead, he’s embarking on a buildup that may become an albatross on his presidency.