Today I want to address something that may seem small, but is more impactful than most people at cons realize:
Please don't Nazi salute at people, even if that person is dressed like a HYDRA Operative. Hell, even if that person is dressed like some fictional Nazi from an anime or Man In The High Castle.
Seriously though, don't dress like a Nazi either. I shouldn't have to explain that one.
This is something I mused about a couple years ago, but my recent 20 Days Of Cosplay posts on Instagram recently reminded me of when I wore a HYDRA version of my SHIELD Agent to AwesomeCon 2015. As I wandered the convention hall, numerous... Individuals walked up to me, and in an effort to do the HYDRA salute from the comics (two arms, both fists) it ended up being a full on Nazi one (one arm, flat palm). Needless to say, I was horrified. I tried to correct as many as I was within shouting distance of, but the moral of the story is... Just don't.
I get it. You want to show how you recognize and appreciate not only the person's cosplay, but also acknowledge the fandom as well. You know the henchmen in the comics and Captain America: The First Avenger all did the salute. Maybe you got it confused b/c there were actual Nazis in that movie as well. To badly paraphrase Abraham Lincoln though, better to keep your arm down than Nazi salute in a convention hall and look like a racist tool.
I see articles on "dressing appropriately" all the time in reference to female cosplayers showing skin, but it's also applicable to choosing a costume what you're symbolizing when you wear it. Perhaps that was on me for choosing to go as a member of an apocalyptic death cult in the first place.
Honestly, I haven't worn the cosplay since. Perhaps it was because all of those gleefully saluting me were white and male, but it would have been unnerving even if they weren't. It made me realize that maybe this was one time I didn't want to be the villain.