I hated having to learn Korean to do TKD. I thought it was the stupidest thing, I'm Canadian in Canada doing a martial arts, why learn Korean?
Now I find I love learning even just bits and pieces of other languages. It's like me saying I'm willing to go out of my way to accommodate you. I find people treat you very different even if you know how to say hello in their language.
As far as Japanese and Aikido I think I'm going to side with the majority here. Aikido is a Japanese martial art. No one is forcing you to take Aikido. Brown belt tests are done in Japanese only, no English. Bunch of reasons for it. Maybe they want to ensure it "stays Japanese" or maybe they want aikidoka to be on the same level so techniques will be called the same thing everywhere you go (which makes a lot of sense).
If you feel so against learning the language then stay at a level where techniques are still called in English, it's always your choice. An honestly, this isn't really learning Japanese per say. It's using Japanese names to identify techniques or a few activities, hardly learning a language.
My sensei is french trying to translate Japanese into English. I've looked at him like he has a toaster on his head more than a few times
Japanese is a good compromise between my English and his french.
I had a judo teacher reply to my questions on why I couldn't use a throw well in sparing with "Your not getting the proper kuzushi". Wow, that helps a lot.
That all comes in time. The longer you train the more you're exposed to Japanese terminology. No one would (or should) expect a white or yellow belt to know this stuff. As your exposed to it constantly you pick up on it naturally. I think it just makes a standard.
Edit: I do remember your frustration Don and have an idea where you're comming from. I think the Sensei in these situations neesd to take a lot of care when explaining the language and terms to beginning students, some people will become a lot more frustrated when trying to understand a foreign language ontop of the stress of trying to learn techniques right?