When our tour guide in Cuba married his high-school sweetheart, the couple had two choices: move in with his parents and grandparents in an already crowded apartment or share the porch with another couple in the tiny dwelling of her extended family. They chose the porch. There were no other options for the newlyweds in Havana in the early 2000s.   Anthony DePalma’s new book, “The Cubans” reminded me of the stories I heard about ordinary Cubanos when I visited the island-nation on a small...