what it would take to "win", but IMO, what it would take to win is a level of brutality that the US isn't willing to do. And good for us that we won't, but the fact that we won't means that almost all the countries over there are ultimately unwinnable for the US.

Saddam managed to keep Iraq 'peaceful' by fear and brutality, and once there was no longer a Saddam to do that, Iraq had all their religious and ethnic differences come right out and start fighting. Afghanistan is essentially the same. The Taliban will only be beaten if you come close to obliterating them militarily and then also brutally suppress what's left of them once a gov't is established.

Again, we're unwilling to do so, and rightly so, but that's the only way many countries in that area have achieved some level of 'peace' for a long time now. Brutally suppress all dissent and any whiff of revolt.