I'm an Iranian-American. I was born in the US and have a completely western accent and world view. However, i'm a bit...racially ambiguous. I'm not exactly "white". My skin tone is darker than the typical white skin tone. I have more of an olive complexion. A lot of people I speak with don't consider me white but some do.
Let's say I am the exact same as I am now. Western educated with a typical western American accent. I am in America where everything is racially segregated. How am I treated by this society?
It would depend how dark your complexion is, where in the U.S. you were, and whether or not they knew you were Iranian. Most likely you would be taken for Native American, Italian, or Mexican, and treated however the locals treated those ethnicities. It is also possible, depending on how dark skinned you are and how Semitic your features, that since you have American speech patterns, you would just be taken for a "white" guy with a tan in areas with lots of year round sun.