Commerce had become a “reason of state” in the eighteenth century. With the publication of Smith’s Wealth of Nations, the idea that free international trade was economically beneficial however gradually gained prominence. The long nineteenth century indeed saw timid – bilateral – attempts to implement the new politico-economic philosophy. Yet the First World War and the Great Depression destroyed almost all trade liberalisation already achieved, and the neo-mercantilist policies of the 1920s and 1930s seemed to turn the wheels of commerce backwards. Nonetheless: after the Second World War the belief that a peaceful world order could only be founded on a stable international economic order emerged strengthened; and a number of institutional attempts to liberalise – and harness – the world economy were immediately made, culminating in the creation of the 1947 General Agreement on Tariffs and Trade.