I think the Afghan people are war tired and will side with whichever side they think is in their best interest.
If the Americans look like they are going to win, more afghans join their side. Otherwise the Taliban. I don't think the Afghans particularly like either of us and unless they are given a valid third option (their country) and nationalistic pride nothing will help them.
Also, the country is so tribal that I don't know if it can truly be unified under a government which caters any tribe at all, like the current one does.
I don't see much hope in Afghanistan atm, mostly due to complete missmanagement.