As the US-led coalition prepares to extricate itself from a combat role in Afghanistan, it is useful to look back and reflect on the policy dynamic of the original involvement. How did the coalition – and more specifically NATO – become so deeply enmeshed in an out-of-area conflict that proved so difficult and where victory was so elusive? Was the engagement the result of deliberate policy or the cumulative and unwilled outcome of a series of small decisions? At what point were exit strategies considered, if at all? And, what are the implications of this for future engagement of the alliance in out-of-area conflicts? Taking a policy perspective as the point of departure, the author finds that the growing involvement in Afghanistan has been the result of a piecemeal decision- making process, self-perpetuating dynamics and a steady goal expansion that led the alliance into a protracted and controversial war.