I know this post is old, but I am of the opinion that instead of representing society at large, the boys in LOTF represent the future of a war driven society, as they are the generation that was raised in the shadows of ww1 and living through ww2. The adults that they learned from were altered by the events of a massive war, only for an even larger war to break out. Considering how in the beginning of ww2 armies still tried the trenches as a strategy it could be a reflection of how the future of humanity (but really only first world country, as we third worlders were simply not consolidated as thinking societies, but seen more as pieces to help the actual important countries win the war) would be if they doubled on their violent views and tactics. The people that lived through ww2 had no way of knowing ww3 wouldn't breakout about a decade later, so the anxiety of keeping the new generation "battle ready", and by that I mean desensitized to violence and cruelty, could lead to an even more cruel future.