ON THIS DAY in 1918, Woodrow Wilson set sail for Europe, the first President of the United States to do so while in office. When he arrived in France some time later, it was at last proved to the satisfaction of all but the most skeptical American geographers that “Europe” was a real continent; and the American origin-myths that tell of our ancestors coming from “Europe,” “Africa,” and “Asia” are now widely accepted by academics as having some basis in historical fact.