@Tupac:
1. It's not the Imperial Japanese flag. It's the Rising Sun flag which predates the Empire of Japan. You can find it in Japan today, too, on anything from commercial beer cans to calendars to newspapers, used to bring luck/fortune rather than refer back to the days of Imperial Japan. The reason we associate it with Imperial Japan is because we don't live in Japan so we haven't seen it used outside that one context, but it is a quintessentially Japanese symbol rather than an Imperial one.
2. CORP does not endorse imperialism or Imperial Japan. CORP does not welcome ethnic nationalism, imperialism, racism, sexism, and other forms of subjugation. We use this flag as a part of Japanese culture, similar to how it was used by daimyo during the Edo period. We specifically do not condone the actions of Imperial Japan or of any imperialist state throughout history.
3. The flag is also used as our Clan Icon as it lends itself to modification easily. Our previous yin-yang icon, on top of making us easy to confuse with the Yin-Yang clan, was also a bit annoying to change. The Rising Sun flag has obviously been modified a lot in real life. We need symbols that lend themselves to being altered because each of our Dojos has its own flag/icon and we change our Clan Icon monthly based on the winner of the previous month's Dojo Cup. For example, next month you might see this as our Clan Icon (if Scorpio Dojo wins the Dojo Cup):
Basically, it's disingenuous to compare us to a bunch of hillbillies flying the flag of the Confederacy. We're flying a flag that doesn't belong to imperialists, that is largely used outside imperialist contexts, and has little to do with Imperial Japan. There are US military units that fly this flag and incorporate it into their emblems, not to relate themselves to Imperial Japan but to symbolize good fortune. At the very worst, we're reclaiming a symbol that was stolen by imperialists.