1) You are confusing copyright and trade marks.

2) Is "American" (or "Chinese", etc.) trademarked?

"EU" is below the threshold of originality; it is not possible to "copyright" two letters, especially without any font or design associated with them.

Perhaps you are instead thinking of trademark protection? Trademark protection, of course, protects trademarks for particular specified industries and is scoped to nations where the holder does business/exists/has jurisdiction.

It's unlikely this will help, but it's 100% certain that copyright ain't gonna apply.