Why so many people including the U.S government ignore the real Meaning of Latino?

The U.S government is using the word Latino for calling just spanish speaking people not even the brazilians are included in official census why? Is not Brazil part of Latin America? is not Latin derive ted language?for what I understand Portugal was part of the Roman Empire and therefore Latin was spoken there Latin was the most Important language in the Western world before !800 s it was the language of the educated people, it was the language of the Romans the thuth Latins or Latinos that was the biggest Empire in Europe 2000 years ago, 50% of the words in English came from Latin and the Alphabet Im using right now is Latin so why call these people Latinos if many of the are mostly Africans or Amerindians or mixed blood people they are just part latino, and thuth Latinos Europeans are not call Latinos, I speak Italian and Spanish and both Languages the meaning of the word Latino means Latin, Latino originally was designated to man that speak Latin and Latina to a girl, but why people ignore this, Hispanic and Latino is not the same Latino means someone that speak Latin deviated Language or something that has to do with Latin language in Romance language, Latino is not a race, is cultural and linguistic term, The U.S doest know the real meaning because they dint anything about entice, HISPANIC means you speak spanish or you are hispanic descends.