In culture, there are certain symbols that stand out as something your brain connects to immediately. The swastika, for example, inspires fear for some, and rage for others. A red hand tells you to stop - it's not something you think about. It's an impulse. After however many years, people grow accustomed seeing certain things. Your mind instantly infers based on what you're seeing. This also happens with names. Even if one is not speaking about a specific person of fame or power, your mind will jump to them. For example, those with the first name Barack will forever be connected with Barack Obama.
In Harry Potter, names and symbols are very much feared. Powerful wizards use insignias to represent a group or culture- and more often than not, this group will not be kind. In class on Friday, we talked about relating the Deathly Hallows badge with the swastika. I think they're connected not only with the whole Grindelwald / Hitler similarities, but also the feelings it inspires. Viktor Krum is very largely offended by the symbol of the Deathly Hallows- near ready to duel Xenophillius Lovegood for simply wearing it. As the holocaust was a large part of world history, the mere symbol of Nazi regime is something that can be frightening, or can be absolutely rage-inspiring. It is considered unspeakable to draw it on bathroom walls or simple graffiti. Not just because of the doodle itself, but because of the horrendous history that accompanies it. It stands for a period of racial prosecution, unbelievable horrors and abuse and concentration camps.
J.K. Rowling not only connects the Deathly Hallows with a simple child's tale, but something that is feared across the globe. She takes it and puts it into "wizard terms" by transforming World War ii. into a period of death lead by a powerful dark wizard. She translates it, but the core is still the same. The swastika and the Deathly Hallows symbol still connect with the fear that is implanted behind it.