In the comics he's over 18, in fact he's married

Much obliged :)

It's not that "everybody does it" and it's therefore morally acceptable, it's that it was the standard of the time. In 1000 historians will look back on us barbarians today and say "how could they have done that!", but we would think nothing of it because what we do is standard. There's nothing uniquely western about the slave trade, as slavery existed in some form in all civilizations.

Britain would've joined the war anyways, the treaty with Belgium wad only an excuse to join

By the lord's name, by what sorcery does this mechanism take flight? Great heavens, it must have come from above, from another land!