"To begin a return of refugees now is unrealistic," said Imtiaz Gul, an Islamabad security analyst and author of "The Most Dangerous Place: Pakistan's Lawless Frontier," a look at militancy in Pakistan's tribal areas.
"Taliban militants are a mobile enemy. They don't sit in one place, waiting for the army or drone to come. The army may have dislodged them from South Waziristan, but many hide here and there, and when they get an opportunity, they will strike."
Pakistani authorities say the military's continued presence in South Waziristan should reassure those who return. They acknowledge that the army doesn't have the manpower to post troops in every village, and say it will rely on cooperation and intelligence from the people to help keep the Taliban from reemerging.
"Unless they're totally erased, the Taliban will try to come back," said Khan, the disaster management official. "We can't expect them to hold wreaths of flowers for returning refugees."