it speaks more to the reaction that this country had to Obama being elected more so than anything that Obama actually did to cause it through his actions.
"Overall, 54% say relations between blacks and whites have gotten worse since Obama became president, including 57% of whites and 40% of blacks. That's up sharply compared with last June, when 43% said things had gotten worse shortly after a racially motivated shooting at a black church in Charleston, South Carolina."