Of all the divisions in America, none is as insidious and destructive as racism. The documentary “The Long Shadow” takes an uncompromising look at America’s original sin—slavery—and traces its history from the country’s founding to the racial divisions that still plague us in the present day. In today’s installment of “Leonard Lopate at Large” on WBAI, director of "The Long Shadow" Frances Causey talks about how her family history led her to make this film and what about it relates to this present moment in our nation’s history.