With the U.S. combat role over in Afghanistan, the country's security now depends on men like Sgt. Maj. Faiz Mohammed Wafa, one of the leaders of the Afghan commandos.
On this day, the Afghan sergeant is screaming at trainees at Camp Commando, a training center built by the Americans in the hills south of Kabul. Two dozen trainees are seated in the dirt in full combat gear. Wafa is trying to teach them the proper way to clear a house, searching room to room for insurgents.
"I told you 10 times," he says. "Hold your weapons correctly!"