"not establishing Zeon as the bad guys by using the World War II-era German aesthetic, but establishing them as the cool guys, devoid of the more proper historical associations that we might assume"
That some anime creators are enamoured with the German aesthetic should be pretty clear to anyone with a passing familiarity with Legend of the Galactic Heroes, suckling as it does so firmly on the teat of 19th Century Prussia. The first few Gundam series were less obviously Wagnerian in their imagery, but the similarities were nonetheless readily apparent; and, as Sean points out in his article, the parallels with the Nazis grew as the franchise developed. Now I'm inclined to agree here, and say that the use of Nazi imagery in Gundam (as with the aristocratic Prussian imagery in Legend of the Galactic Heroes) was done primarily to look cool. Japan tends to view the Second World War in terms of the naval war in the Pacific and the bombing of its own cities by America, with visual reminders of the horrors of the European war entirely non-existent. As a result, there's less of a defined social consensus on what constitutes a valid portrayal of the Nazis in Japanese media.
Brits enjoy mocking Americans who date the war 1941-1945, relegating the invasion of Poland, the fall of France and the Battle of Britain to mere footnotes in the war's history, but in dating the war from 1939, we do the same to the Marco Polo Bridge Incident and the invasion of Czechoslovakia. The point is that each country has its own embedded narrative of the Second World War. The British narrative is tied up with Dunkirk and The Battle of Britain, both of which position us as plucky underdogs, holding on desperately, alone in the face of seemingly unstoppable adversity, but to an outsider, would it necessarily seem like that?
The RAF's defence of Britain against German bombers is certainly a stirring tale, but when you think of the great fighter aces of the war, you have to scroll down a very long list of German pilots before you get to James Edgar "Johnnie" Johnson, whose 34 kills were impressive but no Erich Hartmann. Bottom line: Germany did fighter aces better than anyone, and fighter aces are romantic. The fact that Germany was on the losing side and that these pilots were fighting for a flawed cause just makes them tragic as well as romantic heroes.
The two battles at El Alamein are often feted in the UK as important turning points in the war, and rightly so, but a quick look at the figures reveals just how hopelessly outnumbered the German Afrika Korps under Rommel were in both battles. The British strategy was sensible -- wait until the odds are insurmountably in your favour and then grind the German army into dust -- but it wasn't daring or romantic. Rommel was underequipped and overachieved through his ingenuity. Montgomery was numerically superior and ruthless. Bottom line: Rommel is a more romantic figure. His execution by Hitler for his involvement in the July 20th Plot just makes him a tragic as well as a romantic hero.
The Atlantic naval battles between the Royal Navy and the Kriegsmarine were similarly one-sided. The Graf Spee was outnumbered three to one at the Battle of River Plate; The Scharnhorst was sunk by a fleet of fourteen Royal Navy ships; the Bismarck was sunk by fleet comprised of two aircraft carriers, three battleships, four cruisers and seven destroyers; the Tirpitz was just bombed to oblivion without ever getting to see action. The Royal Navy was ruthless in hunting down and destroying German ships, and even went as far as attacking the French fleet at Mers-el-Kebir to prevent them falling into German hands. Compared to the clenched iron fist that the Royal Navy swung down on any challenge to its supremacy in the Atlantic, the German ships and U-Boats cut lonely figures. Bottom line: German warships operated in a more romantic milieu. The fact that they were outnumbered, outgunned and doomed makes them tragic as well as romantic.
Now imagine: you're a writer and you're planning to tell an epic war story. You have a love of tragedy, and the idea of depicting the lives of soldiers fighting for causes they don't even necessarily believe in, under leaders who don't necessarily have the noblest of motives appeals to you. You want there to be drama, and you want there to be pathos. You look to past wars for ideas, seeking not the most honourable and righteous causes but the situations with the most dramatic potential. It turns out that the protagonists of many of the most dramatic situations of the war also had the nicest uniforms. A big grin spreads over your face and you say, "Eureka!"
So to paraphrase Sean's article, I would posit that Gundam is not establishing Zeon as the bad guys by using the World War II-era German aesthetic, but establishing them as the tragic, romantic and dramatic guys, devoid of the more proper historical associations that we might assume.