Or people for who English is not their first language. In Spanish at least, an "americano" is anyone from the Americas. People from the US are "estadounidenses".
It started with the Mexican-American war of 1846, so that is a viable theory (though the CIA was not yet involved). That's the war Mexicans still teach in every Mexican school with a big famous map showing that California and Texas are Mexican territory unjustly stolen by the USA.
Which should help indicate how good an idea it is to invite more people from that region to our country.