Sgt. John Hunt from Blackshear, Georgia, left, and Spc. Brian Kolessar from Middletown, New York, right, both from the 293rd Military Police Company out of Fort Stewart, Georgia, U.S. play jump rope with local children during a patrol in Kandahar City, so
Credit: Kirsty Wigglesworth / AP

David Kilcullen, architect of modern warfare, sits ensnared in Kabul traffic. It's a chaotic scene that feels more like a drive-through bazaar than a road. A pack of Afghan children tap at the car window, and one boy waves a canister that billows smoke. The boy swears it's incense and will bring good luck – a pipe bomb of happiness. The children gawk at Kilcullen's red hair and ruddy complexion, not noticing that his left hand stays hidden beside his thigh, where it holds a Glock pistol.

"This isn't good," Kilcullen says, his Australian accent perpetually rising. He explains: A band of beggar children is like a neon arrow, pointing the Taliban's spotters toward a Western target. Traffic is bad. Children are bad. The two together can be explosive.

Kilcullen should know. He serves, officially, as a lieutenant colonel in the Australian Army inactive reserves. Unofficially, he is one of the most influential people in the theory and practice of counterinsurgency, and he has helped recast the modern American military, from high doctrine down to the battlefield.

When we reach our destination – an officers school for counterinsurgency, outside Kabul – Kilcullen springs from the car to meet the school's new commander. Colonel Chad Clark is a sharp-eyed veteran of elite counterterrorism units, and when Kilcullen mentions the traffic and children, Clark does something unexpected: He grins.

It turns out Kilcullen had read the street scene wrong. He would have been spot-on a year ago. But insurgency is so fluid, so unreliable, that the opposite is true now. "Anywhere you see a traffic jam, things are all right," Clark says. "Children are a good sign. People pull their kids inside when they sense something's about to happen."

That's good news, Kilcullen says, brightening. Things are looking up in Kabul.

Kilcullen has come to Afghanistan from his base in Washington, D.C., to talk strategy with General Petraeus. The two are good friends, and the general – "Dave" – looks to the 43-year-old Kilcullen for advice. Both have a lot at stake in counterinsurgency: If Petraeus manages to successfully end two of the country's longest wars, the hardest part of any potential presidential campaign would be behind him.

Even though a third of the country is still under the influence, if not outright control, of the Taliban, Kilcullen is ebullient. He has a genius for breaking down any challenge into a series of clear, simplified steps. The first step toward victory here – or at least a dignified exit – is undoing the damage wrought by conventional warfare over nearly a decade. And he is not above trash talking. He caused a stir in 2008 when he called the invasion of Iraq "fucking stupid." It might not have mattered, except he worked at the time as a special adviser to Condoleezza Rice.

Now, in Kabul, he's feeling jaunty again. "We cleaned up their mess in Iraq," he says of the military's old guard, "and now we'll do it here."