Video obtained by CBS News and shot by a U.S. Marine during the most recent firefight with locals shows that as many as 14 suspected Taliban or al-Qaida members were able to slip past Afghan defenses to get within 300 yards of U.S. troops at Kandahar's airport.
"It wasn't until they popped up from behind those adobe buildings and started to engage us that we were able to hit them with our fire," said Marine Capt. Dave Greenwood.
For days now, the Marines have been rolling through local villages trying to prevent another attack; relying on tribal leaders to tell them whose guns to fear most.
The villages are always remote, and in some cases partially abandoned the perfect breeding ground for the heartiest of Taliban to try and regroup. Most agree that to do it they would need the help of locals; some of the very same locals the U.S. depends on for help.
"Half the people out here could be Taliban, and they just decided not to be Taliban for a day," says Marine Cpl. Mike Simmons. "Or you never know who they are, if they're friends or not."
The local forces have been more than willing to help, roaming the streets by day, patrolling unlit neighborhoods by night.
But in a place where allegiances have changed so readily and so often, deciding who to trust is as complicated as the tribal loyalties are deep.
Not so long ago, Wali Mohammad Ibrahimkhiel was a powerful Taliban commander with hundreds of soldiers prepared to die at his command.
But when anti-Taliban troops began their rapid march through northern Afghanistan, Ibrahimkhiel sensed the end of the Taliban was near. So he made a simple and pragmatic decision.
He switched sides.
Now he is an even more powerful commander under Afghanistan's new leadership, with thousands of soldiers at his command.
In other parts of the world, Ibrahimkhiel's choice might be called betrayal or treason. In the world of Afghan warfare it is just strategy.
"This is a normal thing in Afghanistan, because everyone loves their lives and wants to stay alive. We switch sides all the time," Ibrahimkhiel said.
Many of Ibrahimkhiel's fellow commanders made the same choice, bringing with them the soldiers at their command. The defections of these less committed Taliban commanders were partly responsible for the rapid defeat of the hard-line regime.
As Ibrahimkhiel reclines on a cushion surrounded by his advisers in a warm room in Chahar Bulaq, the town he commands 25 miles west of Mazar-e-Sharif, thousands of Taliban prisoners, who either refused to switch sides or did not do it in time, sit in the filthy, cold prison in Shebargan, 55 miles away.
On the floor behind Ibrahimkhiel rests a framed piture of Gen. Rashid Dostum, a northern Afghan warlord who is his new patron.
Under the Taliban, Ibrahimkhiel commanded 800 troops. Now he is commander of the 70th Division and leader of 3,500 men.
"There is no bigger commander in this area than me," he said, a lit cigarette dangling from his right hand. "Gen. Dostum has made me very powerful."
Ibrahimkhiel, 25, first picked up a gun seven years ago because, as the son of a local commander and highway bandit, he was expected to. He joined a local militia run by commanders from his Pashtun ethnic group.
When the Taliban, who were also led by Pashtuns, began capturing parts of northern Afghanistan in 1997, he gladly switched sides.
"We welcomed them," he said. "The Taliban brought peace here and everyone was safe."
But he slowly became disillusioned, he said.
The Taliban would not let him smoke. They threw him in jail for two days once after he defended one of his soldiers against punishment. And then he noticed their foreign allies.
"We saw some Arabs and Pakistanis and Chechens, and I became sad. On both sides of the war were Afghans, but now we had foreigners killing Afghans," he said.
Ibrahimkhiel became convinced the foreigners were out to destroy Afghanistan, and sent secret messages to the anti-Taliban Northern Alliance about his discontent, he said. But still he fought alongside the Taliban.
When the U.S. bombardment of the Taliban began, U.S. forces, sensing Ibrahimkhiel's loyalty was wavering, gave him a satellite phone so he could call Northern Alliance commanders and set up a defection plan, he said.
In mid-October, 500 of his men were stationed along one side of the front line and suffering heavy American bombardment when he invited Dostum's troops into his camp.
They came, the U.S. bombardment immediately stopped, and the two groups chased the Taliban forces from the area, he said.
Three weeks later, when the northern city of Mazar-e-Sharif fell, Ibrahimkhiel knew he had made the right choice and had become more powerful than ever.
"All this territory is under my control," Ibrahimkhiel said of Chahar Bulaq. "I can order everyone around. If I order soldiers to go under fire, they will go under fire. Nothing is forbidden for me."
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