Training: Who, What, Why

Listening to the talking heads on television, I get the impression that a fair number of the increased troops to be sent to Afghanistan will be "trainers". If this is the case, my first question is who will be trained. I assume it will be Afghans. But why do those Afghans - supposedly on our side - need training in the art of war when the opposition, who are mainly Afghans, is doing quite well without the benefit of foreign trainers? What will they be trained in? Winning hearts and minds?