In eight years, you have done so much. Seen so much. You stood at the gates of the Robben Island cell where South Africa’s Nelson Mandela was imprisoned for decades, your arms around your father. You traveled to Liberia and Morocco with your mom to talk with girls about the importance of education—girls who saw themselves in you, saw themselves in your parents, saw who they could become if they continued to study and learn. You attended state dinners, hiked in national parks, met international leaders and managed to laugh at your dad’s jokes during the annual Thanksgiving turkey pardon,...