The United States of America is an embodiment of "manifest destiny", which is a declaration of intent to conquer the sovereign people of the continent.

It’s clearly not a grape!!!

It's quite presumptuous to demand the people of another country refer to themselves in a particular way. You are free to call us whatever you want amongst yourselves. We do it with Germany/Deutschland and they don't seem to mind that much. But we're not demanding that they refer to themselves by our name for them.

Not just Americans. In Portuguese, Americans (that is, those from and of the USA) are often called americanos. In French, américain is much more commonly used than États-Unien.

The Spanish meaning of americano that does not include Americans in this way is very unusual among major Western languages https://en.wikipedia.org/wiki/American_%28word%29#Other_lang.... I don't mean to say that the equivalent of "American" in those languages is the only way to refer to those of the USA, or that equivalents to "USA" and such don't exist. In Portuguese, Italian, and German, however, saying Americano/Americano/Amerikanisch would generally be understood as referring to that of the USA without additional context, as opposed to a Brazilian or Argentinean, in a way that Americano wouldn't in Spanish.