Some people concentrate to much on political descision of dealing with Taliban, which indeed could be a political suicide for a politician. There're other ways how Taliban could come into power, somewhat legally akin to Muslim Brotherhood in Egypt if allowed (and that's was no-brainer after removal of Mubarak) or forcefully, since ISAF withdrawal at this point leaves little chance of Afghan Army to resist.
Security map of Afghanistan as of 2007-2008, not much has changed since then. Taliban is strong in Southern and Eastern regions.








