With Halloween bearing down hard upon us, this seems like a good time to discuss cultural appropriation. A lot of people express irritation when someone from the dominant US culture (white and/or Christian and/or male) attempts to “mansplain” appropriation.
That’s easy to understand: Too often the dominant culture just grabs something without asking either permission or the appropriate use of same.
At the same time, while education can do much to alleviate the problem, cultural misappropriation is not only impossible to prevent, it is also impossible to predict in advance whether something will or will not be appropriate or offensive.
The most blatant bad examples are people from the dominant culture (see above) wearing costumes based on other cultures in a denigrating, mocking context. Drunk frat party with rich white kids dressed as Mexican banditos and their dates as sexy Indian squaws? Don’t pretend there’s any innocence there, pal; that’s the dominant culture’s ruling class showing what they think of anybody Not Them.
But…sci-fi / comic book convention with large size folks of either gender dressed as Sailor Moon? Well, depends…they could be ridiculing those who like Sailor Moon, or they could find something in Sailor Moon’s character that is so appealing to them they want to present as that character in an environment where such activity is appropriate.
Sailor Moon is a great place to start this discussion. She’s a Japanese pop culture character reflecting elements of Japanese folk tradition and Shinto theology, but at the same time the outfit she wears is something the Japanese appropriated from the West (the Germans, in fact) when they raced into overdrive to match the West when Commodore Perry came a’calling. Realizing they were at a distinct technical disadvantage to the West, the Japanese sent scholars around the world to study what the West did and did well, then to bring the best ideas back to their empire and apply them wholesale to their culture.
The “sexy Japanese school girl” outfit of many a fantasy is based on German school uniforms of the 19th century. As the 20th century changed fashion standards around the world, the old Sound-Of-Music style uniforms mutated into more modern, more stylish outfits…and then the Japanese students themselves pushed the envelope even further by individually customizing and accessorizing them, the result being a spectrum now that runs from practical outfits for actual middle school students to elaborate items of fetish wear.
Were the Japanese wrong to adopt the Germans’ school uniforms? Some would argue the West forced them to change, but that’s not true: The West was a threat to Japan prior to WWII but never held direct influence over them (as they had in China or India). The Japanese realized they were working from a weaker position and opted to adopt what they thought was successful in their competitors, but they were the ones who got to pick and choose which elements to introduce, which to keep, which to discard, and which to modify.
Jump ahead 150 years from Perry’s arrival and Japan is no longer seen as a weak and exploitable culture but as an equally dominant one with innovative ideas. So when American fans -- from a wide variety of ethnic and cultural backgrounds -- show up at a convention to celebrate the character, whose culture are they appropriating? Feudal Japan? 19th century Germany? Or some hybrid of both?
Conversely, there are cultural appropriations that, no matter how seemingly benign to the appropriators, nonetheless are fraught with the potential for negative connotations.
Gilbert and Sullivan’s The Mikado (arguably their masterpiece) is a tale of English social mores set in a fantasy Japan; distancing by removing the Englishness of the story and characters from the real setting and transporting it to a make believe Asian country allows Gilbert and Sullivan to work their delightful satirical magic -- which, it should be noted, is always aimed squarely at the English, never the Japanese.
Yet to try to do a classic interpretation of the operetta, with non-Asian actors in vaguely Asian-style costumes and hairstyles attempting to emulate Asian facial features through greasepaint, is to fairly beg for trouble.
It does no good to say the story has nothing to do with the reality of Japan and is just a patina over an examination of English mores, the fact is non-Asian performers traipsing about onstage in a parody of Asian styles and facial features does not sit well with many people.
Nor should it.
One of the great advantages of the stage -- any form of stage presentation -- over a cinematic experience is that if a character points off and says, “Here comes the Mikado!” then whoever walks on stage next is the Mikado, and whatever they are wearing is the Mikado’s costume.
The audience simply accepts it and rolls with it.
My daughter attended Hollywood High and performed or participated in several of their productions. They did a multi-ethnic modern dress (i.e., military fatigues) version of MacBeth with no complaints from Scottish partisans; they mounted an excellent performance of West Side Story despite the challenge of not having enough kids in any one ethnic group to fully staff either the Sharks or the Jets -- the audience simply had to accept that this group of multi-hued teens were Polish and that group of equally multi-hued teens were Puerto Rican.
By comparison, Wait Until Dark was a multi-ethnic piece of cake…
But what one can get away with onstage does not translate as well in film or TV. With very, very few exceptions, movies tend to follow a naturalistic style -- even the ones set in other worlds or other dimensions.
There is an effort in films and TV to make things look “real” and as a result, the forgiveness audiences extend to stage productions is lacking. 
But it is very, very, very rarely acceptable to attempt to pass off an actor of one ethnicity as another.
Johnny Depp uses a Native American great-grandparent to blunt criticism of his portrayal of a fictional Indian, and yet just a couple of movies later he’s playing a real life Irish-American gangster. Robert Downey Jr. narrowly skates the edge of outrage by playing a white actor playing an African-American character and using prosthetic appliances so skillfully applied that at first glance he seems to be genuinely African-American.
We accept Tony Randall playing the over-the-top Dr. Lao because it’s a fantasy movie, Dr. Lao is not really Chinese (not even in the context of the film), and Randall is playing all the other fantasy characters as well, regardless of ethnicity or gender or species.
So he gets a pass, but we cringe in horror watching Breakfast At Tiffany’s as Mickey Rooney dons buck teeth and yellow face to try to act Japanese.
Going back to cosplay, the acceptable rule of thumb is that emulating a character’s costume and hairstyle is acceptable, but altering skin color (unless it’s something decidedly non-realistic, such as Martian green or zombie grey) is not.
Which circles us back to Sailor Moon, a Japanese character with long blonde hair…or is it? The multi-hued hair of Japanese characters do not necessarily literally represent those colors; rather they are a way of Japanese artists to depict the various shades of brunette found among ethnic Japanese.
Scrupulous non-appropriation and impersonation is not possible; while the extremes are pretty obvious there are wide swaths in the middle where people of good will and good intention can disagree.
It’s one thing to don a costume or appropriate some cultural artifact without knowing what it means to the culture one is appropriating it from; it’s another to be invited to share in a cultural experience by a member of that culture.
This is where education is important, and not to put the onus on non-dominant cultures to teach others, but on dominant cultures to look outside of themselves long enough to find out if there is a problem or not.
If you are a sports team with a racially offensive name, and you simply blow off or dismiss as unimportant complaints about that name, you’re not any better than a frat boy with a felt mustache and a dime store sombrero claiming to not need any stinkin’ badges or a sorority sister in a faux buckskin mini-dress and a plastic ceremonial feather headdress making whooping sounds while brandishing a rubber tomahawk.
If you are a member of the dominant culture (again, see above) and you feel threatened or embarrassed by people who complain about how you depict their cultures, maybe you should ask yourself why it’s so important to you to do what you want without having to take the rights and opinions and feelings of others into consideration.
 There are exceptions. The original Star Trek and the early Doctor Who series, not to mention The Muppets, relied heavily on their audiences agreeing to play along with the gag and pretend frogs could sing and a papier mache boulder represented an alien world.
 He gets away with it because the gag in the movie is his “real” character is so crazy and extreme a method actor that he will go that deep into character and manage to pull it off; he would have not been accepted at all if he had actually been trying to play an African-American.
 And this rule doesn’t apply just to dominant culture performers playing US-minorities; Thoroughly Modern Millie has three Asian actors playing Chinese characters, and not one of them is ethnically Chinese.
 What, you thought all Asians had jet black hair? Dark yes, but there’s a wide variety of nuance among them.