These children flock from the bazaars of Pul-i-Charkhi in the poor eastern suburbs of Kabul to work for a few infernal hours on the Mahi Par Pass, but it is better than anything else they could have.

Late last year, they began to experience what life may be like after the Americans leave in 2014.

When Pakistan closed the border to NATO supply trucks in November, the trucks stopped coming, and business for these children slowed to almost nothing. Suddenly, they were out of jobs.

“Business was very low at the time,” said one young man, Ziaullah, who did not know his age but looked about 20. He cut a lonely figure in a dirty green tunic amid billowing fumes on the edge of the cracked road.

“It hurt our business a lot, because usually the drivers of the trucks are paying us money, not the small cars; they usually pay 10 to 20 Pakistani rupees,” or 10 or 20 cents, he said. “At that time I was earning 100 to 150 afghanis a day,” $2 to $3, “so I was dividing the money for different things: 50 for bread, 50 for sugar.”

Pakistan reopened the border in July, and the NATO supply convoys, driven by Pakistani and Afghan contractors, have resumed.

“I am happy if the road is open,” Ziaullah said. “It is good for my business and my family.” Ziaullah is the only person in his family who has a job, and he works so that his five brothers can go to school.