Right, but once that has been accomplished, what then? Declare "mission accomplished" and leave?
There is the Taliban, of course, co-conspirators after the fact. (Legally speaking (AFAIK), conspiracy to murder and, to a slightly lesser degree, conspiracy to aid and abet a murderer's escape are considered worse offenses than the murder itself.)
There was one interesting option that presented itself early, although probably no longer available... Iran.
As you may recall, they offered to 'make nice' and actually aid us in helping to get rid of the Taliban, whom they despise. Bush's reaction of course was to dis them completely... their reaction after that was even then "OK, so we aren't going to allow you to fly over our territory, but still if one of your fliers gets in trouble, we will provide safe haven" - which, incidentally, we did, and they did.
Could there possibly be any way to reclaim that offer, and would we want to?