If it weren't for the fact that the TV set and the refrigerator are so far apart, some of us wouldn't get any exercise at all.
Apprentice is the beginner - the first years you work in a craft in the European sense you are an apprentice. That takes 3 or 4 years. Then you are a journeyman. You can go from one master to another and learn other tricks and other secrets.
Anything that reduces war-related destruction should not be considered altogether immoral.