Contributed by Laurie Fendrich / The revised exhibition, at the Museum of fine Arts in Boston, with 73 paintings and 23 drawings, is a team effort mounted by the museum’s two curators, two guest curators, various museum staff and educators, the critic Homi Bhabha, and a trauma counselor who crafted a statement about “emotional preparedness” for the show. It begins: “The content of this exhibition is challenging. The Museum offers these words in a spirit of care and invitation.” Midway through the exhibition, visitors who find the material too disturbing can leave through a special exit before they encounter particularly vivid Klan imagery.