The overarching Western objective in Afghanistan should be to prevent that country from becoming not just a haven for transnational terrorists, but a terrorist ally as well. That was the situation prior to 9/11 and it would be so again if the Taliban returned to power with al-Qaeda backing. NATO can prevent this indefinitely as long as it is willing to commit significant military and economic resources to a counter-insurgency effort. It cannot eliminate the threat, however, as long as the Afghan insurgents enjoy sanctuary in and support from Pakistan. Alternatively, this objective could be achieved if the Taliban could be persuaded to cut its ties to al-Qaeda and end its insurgency in exchange for some role in Afghan governance short of total control.