At Hillsdale College tonight, Herman Cain said nothing about Ginger White’s accusations. He spoke for roughly 40 minutes, giving a speech that was advertised as a policy talk on foreign affairs and national security. It was curiously light on substance. For an address whose refrain was “peace through strength and clarity,” his views on Afghanistan and other matters remain as unclear as ever. He just seemed out of his depth. When Cain was done, he took no questions. The audience, full of conservatives who would have met him with rapturous approval just a month ago, received him politely but without great enthusiasm. This was not the performance of a candidate who looks determined to battle on.