The Taliban have made a concerted comeback in the past two years; they are the de-facto authority in much of the Pashtun south and east, and have recently spread their violence to parts of the north as well. The debilitating and corrupting effects of the opium trade on the government of President Hamid Karzai is a significant factor in the Taliban’s revival.
The Taliban instituted a strict Islamist policy against the opium trade during the final years of their regime, and by the time of their overthrow they had virtually eliminated it. But now, Lieutenant General Mohammad Daud-Daud, Afghanistan’s deputy minister of the interior for counter-narcotics, told me, “there has been a coalition between the Taliban and the opium smugglers. This year, they have set up a commission to tax the harvest.” In return, he said, the Taliban had offered opium farmers protection from the government’s eradication efforts. The switch in strategy has an obvious logic: it provides opium money for the Taliban to sustain itself and helps it to win over the farming communities.
The impression I've gotten from journalists who have travelled with the Taliban is the insurgents aren't hurting for money. It also costs far, far less to keep a Taliban foot soldier in the field for a year than his Canadian or other NATO counterpart.
If the Taliban aren't hurting for money as a result of drug revenues, have a safe haven in Pakistan and NATO troops keep killing civilians in the battle against the Taliban, then it would seem this conflict has the potential to go on for a long, long time. :(