Norman Barker performed a duet with Judy Garland in the 1948 film “Easter Parade.” His son, Dan, became a pastor, before falling away from his Christian faith in 1984. In 1990, Dan Barker, by then a devout atheist, published an essay, which he titled “An Easter Challenge For Christians.” And he has reissued his transparent attack on Easter every year since then. This year, his challenge appears on a blog hosted by the so-called Freedom From Religion Foundation, an atheist hate group, based in Madison, Wisconsin, for which Barker and his wife serve as co-presidents. In his anti-Easter essay, Barker...