Hyphens, En Dashes, Em Dashes

Q. In a previous Q&A, a curious reader asked you to weigh in on the subject of hyphenated Americans. You responded that “CMOS prefers not to hyphenate Americans of any sort, even when they appear in an adjective phrase.” Were it actually an adjectival phrase, like “apathetic Americans,” I would be inclined to agree; however, I maintain that the examples “African-American,” “Asian-American,” and even “Native-American” (or as I prefer, American-Indian) are all compound proper nouns and must be hyphenated. They are not merely Americans who happen to be African, but rather African-Americans—a distinct ethnic and cultural group. Irrefutable logic?

A. I don’t see any logic in requiring the hyphenation of compound proper nouns when they are used as adjectives. In fact, because they are capitalized, there is no need for additional bells and whistles to signal that they belong together: Rocky Mountain trails, New Hampshire maple syrup, SpongeBob SquarePants lunchbox.