MOUNT SHASTA, Calif. — It is a glorious day in Northern California, and Lewis Elbinger, a 68-year-old Bernie Sanders supporter, is feeling great — or, as he puts it, “high vibe.” In the five decades since he first painted a white peace sign on his forehead, protested the Vietnam War and hitchhiked to India to become a monk, in fact, he has never felt more optimistic about the country than at this very moment. “A consciousness is rising,” he says. A case could be made that this is not exactly so in the sense that Elbinger means it. Donald Trump...