People often ask, "What's your favorite all-time TV show?" I never hesitate to answer: "The Dick Van Dyke Show". Sure, part of it is nostalgia. I grew up with the black-and-white CBS comedy, which premiered 50 years ago on Oct. 3, 1961. It was very much rooted in the Kennedy era, with the pilot having been shot the same day that John F. Kennedy was inaugurated, Jan. 20, 1961...