It is often said that the twentieth century was the American century. The great popularizer of this idea was Henry Luce, who as publisher of Life magazine urged the people of the United States to fulfill what he saw as their historic destiny “to rise to the opportunities of leadership in the world” by joining the fight against Hitler (Luce, 1941, p. 63). In Luce's telling, the American century didn't start at the end of World War II; as Nye (2017, pp. 11‒12) reminds us, conventional accounts of American post-war dominance are vastly overblown. No, for Henry Luce, as for Charles Beard (1922) and for Bertrand and Dora Russell (1923), the American century had begun at the start of the twentieth century, not in its middle. Luce said that in 1919, at the end of World War I, the United States had missed “a golden opportunity, an opportunity unprecedented in all history, to assume the leadership of the world – a golden opportunity handed to us on a proverbial silver platter” (Luce, 1941, p. 64).

Luce is well-remembered for calling the twentieth century the American century, but he is not well-remembered for calling the twentieth century the “first” American century (Luce, 1941, pp. 64 and 65). Luce strongly implied that it would not be the last. Though declinism is a recurring theme among members of the US international relations establishment, there are some who share Luce's point of view. Nye (2015) addresses Luce quite directly in the title of his book: Is the American Century Over? His answer is unambiguously no. Taking into account a multitude of economic, political, military, and cultural aspects of global leadership, he concludes that “the American century is not over … we have not entered a post-American world” (Nye, 2015, p. 125). Wohlforth (1999, p. 37) presciently came to this conclusion two decades earlier, recognizing that “unipolarity is not a ‘moment.’ It is a deeply embedded material condition of world politics that has the potential to last for many decades.”