Who was President during World War I?

Why this is the answer

Woodrow Wilson, the 28th president, and saying just “Wilson” is enough because the first name is optional on the official list. He held office from 1913 to 1921, two full terms, and the whole war, which ran from 1914 to 1918, fell inside them. That overlap is the simple reason he is the answer, but the way the country entered the war tells you more. The conflict began in Europe in 1914, when people called it the Great War. Through his first term Wilson kept the United States out of the fighting. By 1917 that was no longer possible: German submarines had attacked British and American ships, and Germany had approached Mexico about starting a war against the United States. Wilson went to Congress and asked it to declare war on Germany. He had to ask, because Article I, Section 8 of the Constitution gives the power to declare war to Congress, while Article II makes the president commander in chief of the Army and Navy. American troops fought until the war ended on November 11, 1918. Before the fighting stopped, Wilson had already presented his Fourteen Points to Congress in January 1918, a case for the war and a plan for keeping the peace afterward. He then traveled to Paris to help work out Germany’s surrender, and the Treaty of Versailles formally closed the war in 1919. That same year he officially recognized Armistice Day, the holiday that became Veterans Day by a law Congress passed in 1954. One mistake to avoid is answering Roosevelt. Franklin Roosevelt is the answer to the next question, about the Great Depression and World War II, and the other Roosevelt, Theodore, is not accepted here either. If the names start to blur, anchor this one to November 11: the holiday began with Wilson and the end of the Great War.