The Wall Street Journal reports:

KABUL—The Sept. 11 attacks that triggered the U.S. invasion of Afghanistan also uprooted 16-year-old Abdul Ghattar from his village in war-torn Helmand province, bringing him to a desolate refugee camp on the edge of Kabul.

Yet Mr. Ghattar stared blankly when asked whether he knew about al Qaeda’s strike on the U.S., launched a decade ago from Afghan soil.

“Never heard of it,” he shrugged as he lined up for water at the camp’s well, which serves thousands of fellow refugees. “I have no idea why the Americans are in my country.”

In a nearby tent that is the camp’s school, his teacher, 22-year-old Mullah Said Nabi Agha, didn’t fare much better. He said he has never seen the iconic image of the Twin Towers burning. He was vaguely aware that some kind of explosion had occurred in America.

“I was a child when it happened, and now I am an adult, and the Americans are still here,” Mr. Agha said. “I think the Americans did it themselves, so they could invade Afghanistan.”

The theory isn’t rare in Afghanistan, where the Taliban has been claiming for years that infidels invaded Muslim territory to steal its resources.

One would think we would have been countering that propaganda all long, but there’s a big problem: 72% of Afghan adults are illiterate and few villages have television or even reliable electricity. News travels by word of mouth. The Taliban has taken full advantage of that intellectual weakness.

According to a survey of 15- to 30-year-old men in the two southern provinces where President Barack Obama sent the bulk of American surge troops, 92% of respondents said they didn’t know about “this event which the foreigners call 9/11″ after being read a three-paragraph description of the attacks.

Perhaps one way to start winning hearts and minds would be to explain why we’re in Afghanistan in the first place. Perhaps more Afghans will understand our military offensive if they know that terrorists using Afghanistan as a base murdered 3,000 Americans — including Muslims — on 9/11. Just a thought.

But even those who do know are prone to conspiracy theories.

Maulvi Abdulaziz Mujahed, an imam at Kabul’s Takbir mosque who served as chairman of the Kabul provincial council in 2008 to 2009, said in a recent interview that the Sept. 11 attacks were a Jewish conspiracy, a view he says was reinforced by his 2009 visit to New York’s Ground Zero.

“I saw the photos of all those who have been killed in the attacks, and I saw people bring flowers for their loved ones. But I couldn’t find a single Jew among them,” Mr. Mujahed said. “The superpowers wanted a good pretext to invade Afghanistan, and these attacks provided it.”

Even Afghan officials dabble in conspiracy theories:

Abdul Hakim Mujahid, the deputy chairman of the Afghan government’s High Peace Council, a body created to negotiate a peaceful solution to the war, was in New York when the two jets struck the Twin Towers—in his capacity as the Taliban regime’s semi-official envoy to the U.S. and the United Nations.

While Mr. Mujahid says he was saddened by the attacks, he says he still doesn’t believe al Qaeda was responsible for “the unfortunate incident.”

There is one bit of good news. Young, educated people are not only more likely to know about the 9/11 attacks but also sympathize with the United States’ subsequent invasion.

“Under the Taliban, Afghanistan was a terrorist haven, nobody could leave their house, and I wouldn’t have been able to attend university,” says Nasser Hasrab, a 20-year-old literature student from the northern Faryab province. “After the Soviets left we had a civil war, and I am afraid that if the Americans leave, the same would happen again.”

Hopefully individuals like Nasser will become more vocal in the coming months and years.

But for now, the United States must make our reasons for invasion clear. We must fight back against the Taliban’s whispered propaganda. Winning hearts might be more successful if we state our intentions in the first place.