Cool Off on Afghanistan?

A really interesting post by an expert, seeming to suggest that beefing up our presence in Afghanistan might not be a great idea, apparently because it's always been a lawless dusty place and will probably remain so regardless of what we do, so with Al Qaeda in Pakistan, why bother with Afghanistan and risk destabilizing nuclear-armed Pakistan in the process?

But this strikes me as a little too hands off and seems to rely on the assumption that it won't require continued action to prevent the Taliban from retaking Afghanistan.