Newly released video footage shows Nation of Islam follower Noah Green shopping for a knife at a store in Washington just hours before ramming his vehicle into a barrier at the U.S. Capitol. The security footage, captured at District Cutlery, was published by WJLA. Green entered the shop in Union Market just after 11 a.m. on April 2. He bought a carving knife for $300, owner Derek Swanson told the broadcaster. FBI agents went to the store over the weekend and began asking questions. “They asked me for footage from our surveillance camera. I reviewed it, it was about 22 minutes he was in our shop. It was hard to tell a lot from it. He acted very normal, and the footage shows him basically trying to decide what knife he wants to buy at our shop,” Swanson said. “I had heard about the incident, but I hadn’t read too …