The United States of America is the only country in the world with "America" in its name. Calling the US "America" is no more "abnormal" than calling Americans

The United States of America is the only country in the world with "America" in its name. Calling the US "America" is no more "abnormal" than calling Americans norteamericanos (Even setting aside Mexico also being part of North America, what about Canadians?) or estadounidenses (given Mexico also being the "United Mexican States").