Why is Obama referred to as black when he is half white half black?

Blackness is subjective. A mixed race person is considered black when it's convenient but also "not black enough" at other times when it's convenient

Because the black half predominates phenotypically. So people can only really get a sense for half his racial heritage based on visual cues alone.

Because he's a black american president. Blacks used to be property now they run the country.

She doesn't matter the important thing is he's black. That's just the ideology

You are whatever messed up your white.

Who really gives a fuck ... your point?

yeah, he's half Hawaiian and half Kenyon too ... js

Whigger perhaps

Because of the "one-drop" law that is a longstanding U.S. tradition, going back to the slave days. When you look at Barack Obama, you see an African-American. Consider this: Eric Holder, former Atty Genl, has two [b] black [/b] (light-complexioned) parents, as did Colin Powell. If you saw the three standing side by side, would you know who was actually "biracial" ? Obama also self-identifies as a black person, and he has every right to do so.