Then how about they use Black-American? The article is not about blacks in general, it's about black people within the U.S.

Then all would have been well. ;-)

How is it insulting? It just references past ties. Would someone with an Irish heritage be insulted by being called Irish American? I don't care if someone calls me Black or African American or even Black American. If you have a preference, then that's fine. I just found it weird to be insulted by it.

Yes, it references past ties. But how far back should we go? Most blacks in America are here by way of slavery, which happened over 200 years ago. As metamemetics said, if we go back far enough, hell, everyone is African.

Another reason is that the Black-American (due slavery) people have become genetically distinct from their west African ancestors. Many of us have a significant percentage of non-African genetics, through inter-marriage and other happenings. If we want to reference past ties, then why ignore that?

Black-Americans (due slavery) have been here since there was an America, so no need to create the distinction of an African American. The term is meaningless.