Prince George’s County is poised to authorize up to $215 million in special obligation bonds tied to bringing a 6,000-seat Sphere to National Harbor. Seriously? The proposed Sphere would undoubtedly be impressive. The original Las Vegas venue is a giant 17,600-seat glowing orb wrapped in LED screens, with immersive video, sound and special effects inside. A smaller version at National Harbor would attract visitors, attention and plenty of Instagram posts. What it would not do