President Obama considered veteran Harlem Rep. Charles Rangel a political hack and had such little regard for Jesse Jackson that he “effectively banned” the civil rights leader from the White House, a new book claims. The political tome about the 2012 presidential campaign, “Double Down,” says Obama had little patience for “professional left” activists and “vanishingly close to zero” for what a White House aide called “professional blacks.” “Apart from Georgia Congressman John Lewis and Jim Clyburn of South Carolina, Obama had nearly as much contempt for the CBC (Congressional Black Caucus) as he did for the Tea Party Caucus,”...