Blame right-wing blogger Andrew Breitbart. Blame the Fox News Channel, Bill O'Reilly and Sean Hannity. Blame the NAACP, Agriculture Secretary Tom Vilsack and Obama. Or take this as an opportunity to heal our nation's oldest wound: racism.After a doctored tape tarnished Shirley Sherrod's life work and credibility and got her fired, even the president reached out to Sherrod. The former Agriculture Department employee was still weighing her options Friday morning.