It's not equivalent because while "American" can mean "somebody from the Americas" it also has a common usage specifically to mean "someone from the USA". Hardl

It's not equivalent because while "American" can mean "somebody from the Americas" it also has a common usage specifically to mean "someone from the USA". Hardly anyone says USAians, and the phrase "are you Canadian or American" is one readily understood by any anglophone. "Asian" has no corresponding usage in relation to India.