It's a horribly messy situation, and I feel the temptation to just leave proxies or the UN or something and wash our hands of the mess. But I don't think it's wise to yield to such temoptation.
We have an interest in what happens everywhere on this shrinking planet. We need to follow through, to be sure the threat to our safety really is neutralized. And I don't feel comfortable about leaving Muslims in charge. They haven't done such a great job in the past. We really need to hcnage the way these people think, so they won't send more suicidal loons at us in a few years. Ram democracy and civil liberties down their throats.
The UN, maybe? They can't fight a war worth a damn, but they seem to be an adequate police force in places like the Balkans. Maybe bring them in after the war is over. But keep an eye on them. I don't entirely trust the UN. Too much non-democratic membership.
And if the Northern Alliance refuses to yield control, then the war isn't over.
I'm not complaining, mind you. Better the Northern Alliance than the Taliban. All things considred, this is an improvement.