With recent footage of black teenagers cold-cocking random strangers in a deadly game known as “Knockout,” Americans should recognize how badly our country needs a selfless voice of leadership heard in all of our homes. But until the dignified message of someone like Dr. Ben Carson becomes mainstream, Mark Twain’s classic punch to the face has always packed the power to knock some sense in to people who need it the most. Nearly 130 years after The Adventures of Huckleberry Finn was published, Twain’s timeless lessons on race and humanity continue to offer America a remedy to racial bigotry --...