This is if we buy Obama’s genealogical roots.
http://www.guardian.co.uk/world/2007/mar/04/uselections2008.barackobama
Obama’s campaign team have handled the news of his family’s slaving past a bit more casually and a lot less emotionally, issuing a statement saying such a family background was ‘representative of America’. That is certainly true. Slavery was the economic bedrock of the American economy in the South before the Civil War. It would come as no surprise that anyone tracing their family roots back to the pre-war South would find that his descendants had owned slaves.
But more edifying discoveries can come from looking at the past too. Another of Obama’s ancestors, his great-great-great-grandfather, Christopher Columbus Clark, fought for the Union army in the Civil War. As a result Obama can also lay claim to relatives who risked their lives to end slavery. ‘While a relative owned slaves, another fought for the Union,’ said Obama spokesman Bill Burton in a statement. Perhaps it is just another case of Obama’s complex past showing that he can have it both ways
Given the tribe of Obama's Mooselimb Kenyan father, it is likely he had ancestors on both ends of the slave-trading supply chain.