What would you call whatever that japanese underage comic thing is? It features no persons and no one was abused yet it still illegal. I don't object to the term as applied, but I don't particularly feel great about the word 'abuse' being used for cartoon characters since it degrades the experience of human survivors.
Not in the U.S., federally at least, where the justice department's guidance specifies that CP is media which "appear to depict an identifiable, actual minor."