The problem the West has in Afghanistan is there are no 'good' guys to support. Karzai is seen as the best of a bad bunch and so he currently is feted by the West.
Under the Taleban there was no opium trade so why not allow them back into power providing they break all links with international Islamic extremists with the threat of tactical bombing if they misbehave. They would probably be too busy fighting their old tribal wars to be too much of an international problem anyway.
Maybe in a couple of hundred years ordinary Afghanis will be ready to embrace Western ideology but for now it seems an utterly fruitless exercise to attempt to force it upon them, if they prefer to be locked in the past so be it, let them.
It is becoming more and more difficult to discern what exactly is the mission in Afghanistan??