When Britain unilaterally embraced free trade in 1846, proponents at home and abroad widely assumed that the rest of the industrializing world would soon follow suit. But Britain’s economic cosmopolitan trump card received an unanticipated countermove from its competitors; one rival after another instead turned to economic nationalism in order to foster their infant industries at home and to expand their closed colonial markets abroad. Even Britain’s own settler colonies abandoned free trade by the turn of the century. Economic nationalism, not free trade, became the driving political economic force underpinning the century of imperial expansion from the mid-nineteenth century to the Second World War.

British free traders sought to curb this economic nationalist turn, and the United States, Britain’s resource-rich former colony, seemingly contained the most fruitful soil for free trade’s mid-nineteenth-century transplantation. All the early omens appeared promising.