It seems totally wrong to begin with but it has been the case in the past for example in the Armenian genocide that children have had to fight alongside their parents just to ensure their own survival as their capture would mean death. Is it therefore morally acceptable that in a last stand against their certain death to hand them a weapon and tell them how to kill with it? But beyond that if that is in principle ok then is it reasonable to send them on the offensive to secure their own existence and finish off an enemy who would otherwise kill them? A friend of mine put this to me the other day and I can't seem to find a concrete, fool proof answer.