On a Sunday stroll up 16th Street in Washington, D.C., years ago, Lonnie Bunch got a hug and a gentle talking-to from an African American woman.

Mr. Bunch — who at the time was the director of the National Museum of African American History and Culture in Washington, which was still under construction, and now heads the entire Smithsonian Institution — had been very visible in the media discussing the newest of the Smithsonian museums. Read more