[user104658]

People are still very sensitive about WW2 and Hitler, probably because there are still survivors of the period alive today. That's all it is. I agree that it's selectively hiding the facts of history because they're "distasteful", which is ridiculous... They wouldn't, for example, ban a Ghengis Khan costume or any other of the barbaric historical figures (many, it's debatable, as bad as or worse than Hitler) if they lived hundereds or thousands of years ago. Many Roman emperors and pharaohs were just as barbaric as Hitler, but no one would think to ban that sort of costume.

Maybe its just a case of "too soon"? I'd say by 2050, when everyone still alive at the end of the war is dead and buried, it'll be less controversial. By 2100+ when their children are long gone too, it'll be considered weird NOT to see a Hitler costume at such an event.

Then again, I suspect the boys motivation was probably to be deliberately controversial and impress his friends... Rather than an attempt to preserve historical accuracy. Should be used as an opportunity to try to get him to understand the seriousness of that history, though... Instead of putting their fingers in their ears and shouting LALALA until it goes away.