Unless I am mistaken, your quibble was the fact that I was capitalizing "U" instead of using a lower case "u".
I didn't think you had made a mistake. I thought you had picked another trifle to pounce on. I think "Union" has the same meaning as "union."
I sometimes capitalize words to draw attention to them, but it never occurred to me this might be seen as changing their meaning or something.
The point is that there is no such entity as the “British Union”, and there never was. You see, once upon a time, Ireland formed a union with the Kingdom of Britain. The result was not a Union. They never called themselves a Union. Only you do that. And you do it to force your fantasy to come to life. The British Colonies in America formed a Union. Do you understand the distinction between a Union and the word union? If you referred to your own imaginary place as the “British union”, would that be any different than from when you say “British Union”? If so, how so?