The situation is actually pretty clear: there’s a counterinsurgency operation going on that is going to take years to complete and is fraught with risk of failure. The question we need to be asking is: given that terrorists used Afghanistan as a base to plan attacks against the West (remember, this was BEFORE the US invaded the country), is failure an option? On balance, it seems as though continuing the mission in the hopes of reconstructing the country and making the place a bad bet for international terrorists to set up shop is still the best option. The UN seems to agree. Feel free to read my take on Currents at Solidarity With Afghanistan