as usual P concisely identifies the main thrusts, and your prediction has a prescient air to it for me.
my fear is that when ISAF nations start to draw down - this seems inevitable, w Canada for instance having their initial round terminate in 2011 i believe, although i don't know if they will then re-negotiate anything else - they will leave Afghanistan in clearly a better position than when the Taliban were in charge, but nascent Afghan institutions will not be robust enough. (tbc, i don't know anything about the status of ISAF contributing nations going forward in terms of which ones have publicly thought ahead long enough to be able to say 'we'll be in X district through 2013, have no fear' or not. so i could well be chatting out of my arse

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i think it's unlikely the (admittedly re-energised) Taliban - w allies such as a different-from-their-pre-9/11-vintage HiG & perhaps other nasty misogynists - will be able to again exercise national control but we know from their attitudes to medicine and education etc, that in districts where they could take over again, the implications of this for Afghan civilians are clearly monstrously, disastrously catastrophic.
(tbc, just because i am not acknowledging above the pervasive issues of contemporary corruption, the killing of civilians in Nato strikes, contemporary allegations of rights abuses by the ANP, age-old hunger and age-old social conservatism in the country doesn't mean i am some starry-eyed armchair warmonger, just that a costs and benefits analysis - plus the Afghans themselves, in countless polls - has demonstrated irrefutably that the worst elements of this insurgency remain a far, far worse proposition than Karzai and some of his shady hoop-jumping w unpleasant bods.)
also w respect to P and Vim and Polystyle in particular - the COIN/military specialists on this thread AFAICT (i pay far less attention to, say, the boards at Abu M than i do to the aid worker reports at the Canada Afghanistan Solidarity Committee) - i am aware the main international driver in Afghanistan, and her individual ISAF allies, have military objectives there, and although it would be nice if the USA's main purpose in Afghanistan was to improve the lot of Afghan schoolgirls, there are military missions to be had there, i know that.
denying jihadis time and space in the borderlands, and unseating their Islamist landlords has clearly had positive benefits for Afghanistan (to understate massively), granted, but, yes, i am aware, that my pov on the Afghan intervention is a little bit different from, say, P's, which is going to be different again from Dial's, which is etc etc etc.
i don't want to imply i have a reckless attitude toward the lives of armed forces and authority figures in Afghanistan and are only concerned for improvements in the lives of Afghan civilians in total (though that is my main concern tbh).
nor am i advocating some endless 'safe havens' kite-flying mission, where the USA sends her boys off on endless occupations in, say, the
next Yemen, far from it.
BTW P, i have a car-crash rubber necking attitude to some seriously dubious sites sometimes. the "Obama's war" asides i meant in the contexts i'd alluded to were from dicks like Counterpunch, that sort of shower. you probably dislike anti-semitism as much as me, so trust me when i say: don't bother visiting them.