Providing a most balanced view of city’s 375-year history, New Haven Museum has been doing a monthly series devoted to local historical “Heroes & Villains.” The subject of the latest discussion, to be held 6:30 p.m. April 9 at the museum (114 Whitney Avenue, New Haven; 203-562-4184. http://www.newhavenmuseum.org/) was both. “Benedict Arnold: Fallen Hero” follows the patriot-turned-traitor’s entire career, including pivotal moments in New Haven. (It was Arnold who forced the issue of Connecticut joining the American Revolution by storming the New Haven armory and heading to Massachusetts while local civic leaders were still waffling.) The lecture is by Stephen Darley, who’s published numerous books and articles on Arnold. New Haven Museum itself has several Benedict Arnold-related items in its collection, including the portrait which illustrates this article.