The United States was one of the world’s first modern nations and one of the first to break free from colonial rule. It therefore stands at the beginning of the history of economic nationalism. This chapter analyses how nationalist thinking on the economy evolved in the USA from the Revolution to the Civil War. During this era, nationalists shifted from an outward-focused system aiming for economic development to an inward-focussed system based on protection. Developmental ideas were first championed by Alexander Hamilton, but his elitist conception of economic policy did not sit easily with the democratising ethos of the new nation. Economic nationalism became a mass movement as intellectuals like Daniel Raymond, politicians such as Henry Clay and activists in the mould of Mathew Carey jostled over questions of trade, manufacturing and banking. Instead of Hamilton’s close relationship between government and capitalists, the new movement put the everyday American producer at the centre. As it did so, isolationist ideas came to dominate. The intellectual capstone of this strand was provided by Henry Carey, whose influence would entrench a distinctly protectionist ‘American System’.