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O ne day, I was leaving the church where I work when an angry woman stopped me. She threw a bag of garbage into the encampment in our yard and told me that a person had started sleeping in hers—and that I needed to tell her how she could find out who it was and make him go away. I suggested that she ask the person himself. She stared at me and exclaimed, “But he takes drugs!” “You can still ask him who he is,” I said. And she stormed away up the street. I tell this story not primarily to illustrate how I have come to be seen as responsible for all homeless people within about...