The Democrats can run, to paraphrase Muhammad Ali’s rebuke of a timid opponent, but they can’t hide. Hillary Clinton is turning her campaign into a game of hide-and-seek, and the party is terrified. Some leading Democrats are beginning to say out loud what they have said privately for weeks. What she thought would be a cake walk to Philadelphia and the 2016 nomination is beginning to look like a cornbread walk, and cornbread has no icing. She took a spanking on the Sunday talk shows, with her party critics focusing on her reluctance to speak up on several key issues,...