Pajistan is going to have to sort out their own problems, with support from other countries.  Foreign troops in Pakistan in a combat role will merely make the situation worse.

 

The UK has repeatedly stated they're are in Afg for the long haul, there's not reason to think otherwise.  However, extensive experience with counter insurgeny also means that they know thay are are going to have to whittle away at the Taliban by political means as well as military.  It's also clear that 'Taliban' is a broad church and there are undoubtedly elements that can be brought over to the govt side.  UK is clearly smart enough to want to pursue this line as well as military action.