On March 4, 1917, President Woodrow Wilson gave his second inaugural address. "We are provincials no longer," he declared. "The tragic events of the thirty months of vital turmoil through which we have just passed have made us citizens of the world." Five months before, he had been re-elected on the slogan: "He kept us out of the war." But in the meantime, the Germans had resumed unrestricted submarine warfare. By the time Wilson spoke, he had resolved to side with the Allies. The true significance of American intervention in a European conflict would extend far beyond its ultimately decisive impact on the war itself. Wilson grasped that the United States was acknowledging that its "manifest destiny" now embraced defending liberty and justice, not only on a continental but on a global scale: "There can be no turning back."
Wilson was drawing on a long history of thinking about what it might mean to be a citizen of the world, going back at least to Immanuel Kant's vision of "perpetual peace". Even Machiavelli recognised ethical constraints on rulers, as Phillip Bobbitt shows in his new study of the Renaissance sage, The Garments of Court and Palace. What we would call genocide and ethnic cleansing "are such vile practices, not only incompatible with a Christian way of life but with any civilised form of living, that every man should abhor such methods and decide to live as a private citizen rather than rule at the cost of such devastation to others". John Stuart Mill, speaking to the Commons in 1867 on "England's Danger through Suppression of Her Maritime Power", denied that his argument had "even a tinge of nationality about it. It is on the broadest cosmopolitan and humanitarian principles that I rest the case." This "cosmopolitan patriotism" caused him to reject isolationism, of the kind now advocated by libertarians such as Rand Paul, as "a principle of utter selfishness".
In an important article that appeared last month in Commentary, the distinguished American diplomat and neoconservative thinker Elliott Abrams argues that Barack Obama sees himself as a citizen of the world. He set out this idea in the celebrated speech he made in Berlin during the 2008 campaign that catapulted him into the White House. "Tonight, I speak to you, not as a candidate for president, but as a citizen — a proud citizen of the United States, and a fellow citizen of the world." Obama told the ecstatic crowd that "the burdens of global citizenship continue to bind us together". He was greeted like John F. Kennedy, whose speech in 1963 had reassured Berliners that America would not abandon their city.