SARAH PALIN and Al Sharpton don’t ordinarily have much in common, but they achieved a rare harmonic convergence at Michael Jackson’s memorial service. When Sharpton told the singer’s children it was their daddy’s adversaries, not their daddy, who were “strange,” he was channeling the pugnacious argument the Alaska governor had made the week before. There was nothing strange about her decision to quit in midterm, Palin told America. What’s strange — or “insane,” in her lingo — are the critics who dare question her erratic behavior on the national stage...