Is Steven Van Zandt content with having spent much of his career in what might have been perceived a sidekick role? The answer is yes, he told Bruce Springsteen during a chat between the two that was webcast Tuesday evening. And maybe that’s just the sort of thing you’d be expected to tell the boss… or the Boss. But this applied not only to Van Zandt’s longstanding stint with Springsteen’s E Street Band but also to his role on “The Sopranos,” since, in a parallel television universe, the role of Tony Soprano might have gone to Van Zandt.

The actor-guitarist’s most-valuable-supporting-player parts in two of the great pop-culture phenomena of our lifetimes came up in a conversation celebrating the publication of Van Zandt’s new memoir, “Unrequited Infatuations: Odyssey of a Rock and Roll Consigliere (A Cautionary Tale).” The two rockers also discussed the social...