Unlike Steven Spielberg's Lincoln, an exploration of a literary figure as flawed as Twain is a tough sell to both social media-centric, smartphone-owning Millenials and Baby Boomers brought up during the Civil Rights era.   On both sides of the spectrum, there will be Americans who could care less about his groundbreaking use of American vernacular in literature, who would wince at his minstrel-style portrayal of slaves,  who need to believe that the words and thoughts of Twain belong to an America that is no more.