Uganda, March 7 -- Nothing is as frustrating as witnessing someone struggling to change their life and failing every time. This is the kind of frustration I feel whenever I bump into a former student of mine whose life has been stolen by addiction. Ian, my once brilliant student is a sad and saddening shadow of his former self. Emaciated and frail, he can hardly meet my gaze anymore, when we meet early in the morning on one of his purposeless journeys.

At dawn, with the hope that a fresh day brings, he seems determined to do something about his life as he greets you politely and offers a few coherent words. Meet him a few hours later after a few rounds with his drinking buddies in the local kafunda and he will be a different person. The ...