Stanley Crouch wrote in a New York Daily News piece "Obama's mother is of white U.S. stock. His father is a black Kenyan," in a column entitled "What Obama Isn't: Black Like Me." During the 2008 campaign, the African-American columnist David Ehrenstein of the LA Times accused white liberals of flocking to Obama because he was a "Magic Negro", a term that refers to a black person with no past who simply appears to assist the mainstream white (as cultural protagonists/drivers) agenda. Ehrenstein went on to say "He's there to assuage white 'guilt' they feel over the role of slavery and racial segregation in American history."
Who wrote about Obama in a Time Magazine piece?