[SPOILER ARLERT: Don't read this if you haven't read the scans and don't want to be spoiled]
I think we can start by saying Isayama is a nationalist and I've heard people say the way he draws Titans is somewhat anti-semitic.
The lesson of this serie also seems a bit reactionary, the fact that "walls work" for example, even if they end up not working so much in the end.
The genocide versus self annihilation aspect is also to be discussed I guess. On the subreddit, you can see many people that are pro Eren, pro destruction of the entire world. I guess if one thing can be said about this series is that there are really no actual good guys, everyone is a killer and all factions suck; whether that's good depiction of politics or not, I couldn't say.
A big part of the story is how nationalism is bad though, the nationalists are never portrayed as good guys.
My question is what kind of analysis does one come up with when one takes the fact that Isayama holds rather strident nationalist opinions into an analysis of AoT. And one must also look at the subtext available as well. The series is rather long and appears to shift its ideological perspective several times over its course. But when one looks at the constants, at least one interesting thing pops up. Mikasa and Dot Praxis, named after two imposing prescences from Imperial Japan, seem to be two characters that are unambiguously good-fortresses almost, though Dot Praxis appears far less in the story.
A bit late in my response, but allow me to explain why I said that.
While it may be important to view a story with all subtext available, I don't believe it has a huge bearing in the case of SnK for a couple different reasons, first being that there does not seem to be any obvious ideological slant towards nationalism in the overall messaging of the show. Let's say you decide to weigh back in the author's support of nationalism into your analysis. What exactly does that change? The only new thing you come away with is the characters who are named after "imposing presences from imperial Japan." One of which is barely a character except for her desire to protect Eren and the other is an eccentric/perverted general who only just narrowly decided not to betray Erwin and the Survey Corps in favour of the monarchy.
The reason I don't think Isayama's support of figures from Imperial Japan is all that important to the overall messaging of the show is that as far as I can tell he's just an ill-informed person who holds a view that is unfortunately all too common in Japan, and probably doesn't have any coherent political ideology to go along with it. If there was obvious support for nationalism in the show, I may be inclined to think otherwise, but if there is any overall moral stance the show takes it's that nationalistic and imperialist tendencies are a hindrance to attempts at internationalism and lead to horrific bloodshed.
If you and I were to have a real point of contention, I think it would be whether or not subtext is always important. And I think it is. Always. Without subtext, as well as context, one must accept all sorts of disagreeable arguments at face value. Arguements such as :"Capitalism has lifted more people out of poverty than anything in history!", "I'm wearing this confederate flag cuz States Rights!" and of course: "Nah dude, she's really 5 thousand years old - she just looks ten!"
I would also say that popular entertainment has been weaponized since before the Illyad. I don't know about you, but I virtually have never paid a dime for manga or anime. And as they say, if it's free, then the product is you. Few would argue that American popular entertainment is thinly disguised propaganda and jingoism with Uncle Sam providing documented support and guidance from at least World War Two and the inception of television. Why give the Japanese govenrment/entertainment complex less credit for promoting its perceived interests, which would inherently be right wing, in it's most valuable cultural export . One can see at least two separate levels of subtext that Isayama is operating on and yet you refuse to give him credit for even having a coherent political ideology. The fact that you and I are on this particular message board means that we have something of a coherent political ideology between us. Would not Isayama, a considerably more accomplished gentleman than ourselves(I'm assuming), also have a reasonably well defined political outlook.?
And yes, if the only allusions to Imperial Japan or uncriticized fascist symbology were Mikasa and Dot Pixis, then I too would have to agree that that was a bit thin. Unfortunately, you also have commanders Erwin (smart like a fox-a Desert Fox perhaps- Isayama made sure to give the character the same birthday) and Hange (Who goes all anime-adorable giddy with the prospect of experimenting on Erin and the other titans), likely loose homages to Rommel and Mengele. (Levi is still giving me trouble. I'm almost convinced that Mengele is represented by both Hange and Levi with Hange being "the Good Doctor" and Levi the literal "Angel of Death" . ) Even more abstract, yet present enough to speculate upon, are the similarities of the Scouts, a small group of determined like minded individuals who impose their will upon the government and ultimately the whole population with the army proving to be along for the ride/a force for good, to another group of guys determined to make Germany great again. He is pretty heavy handed with his allegories comparing the Eldians with Jewish people, but slightly more cautious with his admiration for Nazis and their ideals. He basically tries to have it both ways, like a Republican reminding you that Republicans freed the slaves. But to be honest, my belief is that the entire layer of Nazi/Jewish subtext is to provide subterfuge for his real goal - you guessed it - Japanese nationalism with the Japanese as god's “Chosen People”.
And allow me to apologize for not adding any context to my claims of Japanese nationalism. First of all, it doesn't spring from a vacuum. 75 years after WWII the US military still occupies Japan. To my knowledge there is no discussion of ever handing it back. No one says the words “occupied Japan” these days, but it is still the fact on the ground and many Japanese are justifiably unhappy about it. To add insult to injury, the same fascists who dragged Japan into WWII and turned Asia into a giant crime scene were for the most part let out of jail after the war and put back in charge. They stay in charge through not upsetting their American overlords, your usual symbiotic relationship with big business and an overt and explicit alliance with organized crime. The Japanese people in general would be happier with the US military gone, but the US is already considering utilizing Japan as an armed and fighting buffer against China and the right wing nationalists see this as a ticket to a long dreamed of re-arming, something that your average Japanese citizen is not excited about either. Nevertheless, in this situation, nationalism of one sort or another is something that naturally finds a very receptive ear in Japan.
In AoT, the Eldians can be seen representing three japanese groups, the decadent brain washed pacifists, the self hating Marley dwellers and the Survey Core – the restorationists. The Eldians are heirs to a glorious legacy and the power to rule the world. Their past rule was one of prosperity for all. This can easily be seen as the Japanese “Co Prosperity Sphere” where a recently modernized Japan brutally sought to acquire colonial possessions in Asia under the rhetoric of a civilizing mission. Read up on it. Blood curdling stuff. The Japanese pacifists, represented by the decaying Eldian elite have not only locked the population inside of a “prison” with its isolationist policies, it has not taught the population its history (erased their memories) and endanger the entire population with their cowardice toward foreign threats. The Japanese who do the unthinkable in questioning Japans role in WWII can be seen personified in the Eldians residing in Marley (the Zeke faction) who are seen as violently self loathing and willing to commit genocide to atone for the perceived past crimes of the Eldians. There is also the possibility that they represent their asian “cousins” , the other asian countries that easily can be considered “existential threats” in the minds and rhetoric of a Japanese nationalist. The only true “heroes” are the scouts led by Erin, heir to the restorationists' struggle. It is this struggle that propels the plot and establishes the “heroic” and “non-heroic” characters and his goal is the restoration of Eldian supremacy. As the series winds to an end I am aware that the zealotry of the main character has alienated his core allies, but I have my doubts that the story will end with an unsympathetic portrayal of said protagonist. I'm sure the ending will be somewhat disturbing though.
I'll close by mentioning an important scene thats also frequently available as promo clips. Though Zeke and crew are the representatives of asians critical of Imperial Japan, Zeke himself is a hairy blond foreigner, a favorite bad guy type for a lot of asian action based entertainment. The scene where Levi, the smaller asian looking character neatly slices the shirtless hairy foreigner out of the Beast Titan before proceeding to violently chastise him reminds one of the at least three times Bruce Lee does the exact same thing to a giant blonde at a pivotal moment. Okay, Chuck Norris doesn't count. And it seems like nationalism fan service at its most obvious. My apologies for the verbosity. Quarantine and all. Lot of time on my hands.