Assuming you mean people from South America, not southern America, it is because South America is a continent made up of different countries and to avoid confusion with USA, they go by either "South Americans" or their own nationality- e.g. Argentinian, Brazilian, Peruvian and so on.
Visit any country in South America and if anyone asks, "Where are you from?" and you answer, "I am an American/" They will correct you and tell you, "You mean North American." All South Americans are Americans. The inhabitants of the United States of America are called North Americans or Norteamericanos. The South Americans probably have more rights to the name. Just a few years after
Columbus, one of the first explorers was AMERIGO Vespucci..He never set foot on North America, but did visit South America. He signed all his maps AMERIGO and the name just stuck.
Well its like saying why aren't Mexicans called Americans since they live in North America. North and South America are just continents that contain individual countries.
TECHNICALLY yes, they are "american". But if you walked up to an Ecuadorian or a Colombian, and called them american, they would probably look at you funny. The same goes for people from Mexico and Canada. Even Puerto Ricans (who are citizens of the United State by birth) would think this was weird. We generally consider someone from the continental United States (including Alaska but not Hawaii) to be "American".
They are called w/e country they are from.
Chileans, Brazilians, Argentinians, etc.
North America has Canadians, Americans, and Mexicans.
If you call a Mexican or Canadian an American, Im sure they will stab you.
We ARE americans (i'm colombian btw) but the imperialistic and egocentric conception of USA about herself has made the word "American" be understood as "citizen of the United States"
I think according to your logic then Canadians should be called american. We are not called americans because we are in North America, we are Americans because we are the United States of AMERICA. Idk that's my thought
I'm really courious and want to know thanks!