Is this a regional thing (Assuming it's a synonym for American. Google tries to correct me to Usain Bolt, then brings up a page of Usian Bolt typos.)
Is this a regional thing (Assuming it's a synonym for American. Google tries to correct me to Usain Bolt, then brings up a page of Usian Bolt typos.)
Note that in Spanish the term Estadounidense (note the similarity to "Estados Unidos") exists, though I don't know how much it's used.
Of course, it's an uphill battle, especially when you consider that the official name for Mexico is Estados Unidos Mexicanos.
And I don't think this usage is particularly "inconsiderate", it's just a quirk of language.
That's seems like it's a pretty silly sentiment, since in common English speech that's exactly what 'American' implies.
As you yourself note, USian could just as easily refer to someone from the United States of Mexico.
I personally think it'd be salutary for our republic if my fellow Americans would refer to themselves as New Yorkers, Californians, Georgians, Texans &c. rather than as Americans (just as Germans, French, Dutch, Danish refer to themselves), but that's a different discussion altogether.
Anyway, I'm not really advocating for one side or the other. In common usage "American" definitely relates to the US most of the time.
I can understand the annoyance of people from other American countries, though. Surely Nigerians, Eritreans, etc. would have a reason to be frustrated if "African" came to refer particularly to "South Africa" and not to the continent.
I think in Mexico they call Americans norteamericanos — but of course both they & Canadians are North Americans.
I don't think there's any reason not to call Americans Americans.