Should people just pretend that they are mixed?

American's don't say they are "mixed". I have never heard that terminology and I am an American. The only I tine I have ever heard that term is by old people referring to someone who is mulatto. However, America is a very young country. Most American's know where their ancestors came from because it was typically a Grandparent or Great Grandparent. Basically not very far removed. So you can say to most American's "what is your ancestry" They will know the percentages, like myself I am 1/2 Polish, 1/4 Czech 1/8 English and 1/8 Irish. Czech was spoken by my Grandmother and Great Grandmother didn't even speak any English. I do NOT think I am Native American or Black so I am not sure where you got that idea. I also don't know where you go the idea that Italians stayed in NY. America is a huge melting pot. Yes we familiar with our personal histories because the country is so young, but we all consider ourselves American first.